5C - Public hearing for the repeal and reenactment of the General Design Guidelines for Boulder Historic Districts and Individual ...nges to Section 3.7, 3.8, 8.2, 8.3 and 9.0MEMORANDUM
November 7th, 2007
TO: Landmarks Preservation Advisory Board
FROM: Susan Richstone, Acting Long Range Planning Manager
Chris Meschuk, Historic Preservation Planner
James Hewat, Historic Preservation Planner
Marcy Cameron, Historic Preservation Intem
SUBJECT: Public hearing for the repeal and reenactment of the General
Design Guidelines for Boulder' Historic Districts and Individual.
Landmarks including changes to Section 3.7 (Windows, Storm
Windows and Shutters), 3.8 (Doors and Storm Doors), 8.2 (Energy
Efficiency), 8.3 (Mechanical and Utility Facilities) and 9.0
(Definitions), as Administrative Regulations pursuant to the
rulemaking procedures set forth in Chapter 1-4, B.R.C. 1981.
PURPOSE:
The purpose of this item is for the Board to: review the proposed
administrative regulations/revision to the General Design Guidelines regarding
window and door significance and condition assessment for Landmark
Alteration Certificates on contributing structures in local historic districts and to
repeal and reenact the General Design Guidelines.
T'he General Design Guidelines were originally adopted in 2003. The public
notice published in the newspaper as part of the rulemaking process cannot be
located and so it is necessary to repeal and reenact the General Design
Guidelines as part of this review. The majority of the changes made are in the
sections conceming the replacement of windows and doors and energy
efficiency.
The Landmarks Board is being asked to repeal and reenact the General Design
Guidelines including the proposed changes, as part of the rulemaking procedure
for adopting administrative regulations Rulemaking, Chapter 1-4, of the Boulder
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Revised Code. To this end, staff recommends that the Landmarks Board adopt
the following motion:
The Landmarks Board recommend the repeal and reenactment of the General
Design Guidelines are as part of the procedure to adopt administrative rules, per
Rulemaking, Chapter 1-4, of the Boulder Revised Code, finding that they are
consistent with the City`s Council's January 16"', 2007 Historic Preservation and
Environmental Sustainability Integration Policy Direction.
BACKGROUND:
In 2006, the Landmarks Board and the Environmental Advisory Board jointly
sponsored a project to determine whether the city's policy on retention of historic
windows and doors should be modified to allow owners of historic properties to
install new windows & doors for energy efficiency reasons. On January 16, 2007,
the City Council reviewed the finding§ from the Historic Preservation and
Environmental Sustainability Integration Project.
At that time, the City Council provided direction to change the city's policy
regarding historic preservation and environmental sustainability as reflected in
Revised Option B developed by staff and the ad-hoc committee as part of the
year-long project (see Attachment B ,j_or all the options presented to the Citu Council on
Ianuaru 16'h. 2007). Specifically, the January 16w, 2007 direction given to staff by
the City Council called for staff, the Environmental Advisory Board, and the
Landmarks Board to:
1. Modify the Historic Preservation Guidelines and Green Points Guidelines to:
a) Review applications for window and door replacements on a case by
case basis taking into consideration location, historic character and
value, and relative condition (see "e" below).
- Primary elevations ("front") -character defining historic windows
and doors must be preserved and should be rehabilitated and fitted
with a storm system to improve energy efficiency. If windows are
non-historic (out of the defined period of significance for the
building or district in which it is located) they may be replaced
with energy efficient windows that closely replicate what were on
the building historically.
- Secondary elevations ("side') - in most cases character defining
historic windows and doors should be preserved and should be
rehabilitated and fitted with a storm system to improve energy
efficiency. Replacement may be appropriate if they are not
character defining. If windows or doors are non-historic (out of the
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defined period of significance for the building of district in which it
is located) they may replaced with energy efficient replacements
that closely replicate what were on the building historically.
-Tertiary elevations ("rear') - in most cases windows and doors
may be replaced with energy efficient replacements. If windows or
doors are deemed to impart exceptional character or value to the
building they should be rehabilitated and fitted with a storm
system to improve energy efficiency.
b) Develop and implement clear and objective administrative regulations
to use in determining the historic character and value of existing
windows on designated historic buildings.
c) Encourage property owners to rehabilitate and weatherize historic
windows and doors by weather-stripping and installing additional
glazing.
d) Encourage the installation of storm windows that match the materials,
proportions and profile of the underlying historic window as closely as
possible.
e) Allow replacement of windows and doors deteriorated beyond repair;
deterioration to be determined by standardized criteria for evaluation
of window condition (to be developed and adopted by staff and the
LPAB as administrative regulation). Replacement windows and/or
doors should replicate the material, design and dimensions of the
original windows and/or doors as closely as possible.
f) Encourage solar collectors and skylights to be placed in inconspicuous
locations, however, as new solar collector technologies emerge with
less noticeable collectors, more flexibility should be given to solar
collector placement.
g) Allow shutters where there is historic precedent.
2. Continue work on a brochure that outlines techniques to make historic
buildings more energy-efficient.
3. Evaluate options for the city to take more proactive measures to improve the
energy efficiency of historic buildings, and discourage the demolition of
historic buildings and removal of historic building materials.
4. Work with the EAB and LPAB to revise the Historic Preservation and Green
Points guidelines to resolve other historic preservation/ environmental
sustainability issues identified by the project including adding Green Points
for: rehabilitating historic houses, installing storm windows and doors to
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f~ ~daltame G ~ 3
historic windows and doors, weather stripping and sealing of leaky historic
windows and doors.
5. Report back to the City Council by October 2007 on the implementation of the
above 4 items. At that time determine whether annual updates to the Council
on energy efficiency historic preservation issues should continue.
Over the past ten months staff, the Environmental Advisory Board, and the
Landmarks have been working toward implementing these policies. On October
3~d, 2007 the Landmarks Board initiated the rulemaking procedure for revisions
to Sections 3.7 (Windows, Storm Windows, and Shutters) 3.8 (Doors and Storm Doors)
8.2 (Energy Efficiency) and 9.0 (Definitions) of the General Design Guidelines (see
Attachment A
On October 30'", the City Council reviewed and approved revisions to the Green
Points program which include changes to give credit for the retention and
rehabilitation of historic doors and windows on designated buildings as well as
encouraging the recycling and reuse of historic materials.
Since January of 2007, there have been two requests for the retrofit' of historic
windows with insulated, thermal pane glass. Both cases were referred by the
Landmarks design review committee to the full Landmarks Board for review in a
public hearing. In the first case, the property owner's request was denied on the
basis that all of the windows proposed for replacement (on the front and sides of
the house) were of high historic character, value, and were in relatively good
condition. That decision was called up by City Council. In the second case, the
Board approved the retrofit of the windows with thermal pane glass on the sides
of the house finding that they were not of high historic character and value, but
denied the retrofit of windows on the front of the house considering them to be
of high historic character and value and to be in good condition.
Individual property owners can benefit from state tax credits for rehabilitating a
historic property. Taking steps to conserve energy can save money and be an
economic benefit to building owners. The tax credit program requires that work
be consistent with the city's historic preservation design guidelines and the
Secretary of the Interior's Standards for Rehabilitation.
~ The revised guidelines define retrofit as, "In a rehabilitation project, the installation of
new materials into existing fabric. For example, a retrofitted window would be the
installation of new glass (i.e. low a glass) that is fitted into and existing window sash".
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~~~~ia it>~a $ Pttr,~ R
Below is a summary of how the General Design Guidelines are proposed for
revision to reflect City Council's direction as outlined in Revised Option B. Item
1 relates to revising Sections 3.7 Windows, Storm Windows, and Shutters and 3.8
Doors and Storm Doors, 8.2 Energy Efficiency, and 9.0 Definitions of the General
Design Guidelines.
Revisions to the General Design Guidelines:
3.7 Windows, Storm Windows, and Shutters & 3.8 Doors
City Council Direction Revisions Made
Review applications Revisions to the guidelines give further direction for
for window and door determining the significance based on the location and
replacements on a case importance of the window. This is achieved by
by case basis. Develop identifying the location and then defining the
and implement clear significance of the door or windows as, very
and objective historically important, historically important or non-
administrative historic. These terms are fully defined in Section 9.0
regulations to use in (Definitions).
determining the historic Avery important window or door would be one that
character and value of is substantially intact and retains its integrity from the
existing windows on period of significance. It can be further identified as
designated historic very important by virtue of its craftsmanship, style,
buildings. and materiality.
A historically important window or door is one that
has retained substantial integrity, and is important to
the overall design or style of the building.
Lastly, non-historic are windows or doors that have
been replaced out of the building's period of
significance, and are inconsistent in materiality, style,
pattern or proportion of the historic window or door.
This classification system aims to provide clearer
direction for determining the significance of a window
or door and whether repair or replacement is
appropriate.
Review applications for A hierarchy of historic building elevation has been
window and door explicitly defined in the revised guidelines as follows:
replacements on a case The primary elevation describes the front or principal
by case basis taking face of a building; or any side that faces a public right
into consideration: of way or open space. A secondary elevation describes
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location the sides of the building, where there is less visibility
from the public right of way. The tertiary elevation
describes the rear of the building, where there is
typically little or no visibility from the public right of
way. By identifying the elevation of the proposed
window or door replacement, the impact on the
building as a whole can be measured. These terms are
fully defined in Section 9.0 (Definitions).
Review of applications The revised guidelines provide a condition evaluation
for window and door form and list specific criteria for determining when
replacements on a case replacement is necessary. Based upon the analysis the
by case basis taking window or door is characterized according to a four
into consideration: class system; adapted from the Secretary of the
relative condition. Interior's Standards for Rehabilitation.
Class I, routine maintenance, describes the simple
upkeep of a window or door, which may include paint
removal, repairs to the frame, re-glazing, weather-
stripping, caulking and repainting.
Class II, stabilization, includes elements that have a
small degree of deterioration but which can be
repaired by patching, water-proofing, consolidating,
and re-gluing the existing material.
Class III, partial replacement, describes windows that
are partially damaged, but that can be repaired
without a complete replacement. This includes damage
to muntins, bottom rails and sills.
Class IV, total replacement, is for windows that have
been damaged beyond repair. This includes a
completely rotted sill, warping, or a combination of
Class III repairs.
Allow replacement of When a window or door has been determined as Class
windows and doors IV and a replacement is deemed necessary, an
deteriorated beyond appropriate replacement must be approved by
repair; deterioration to providing information in one of two ways:
be determined by 1) Submit side-by-side comparison drawings of one
standardized criteria for vertical and one horizontal section each of the existing
evaluation of window window or door and the proposed window or door.
condition (to be The drawings must show the profilespo~f~,~,muntins,/~
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developed and adopted meeting rails, sash frame, and moldings. It should also
by staff and the LPAB show the window's relationship to the existing wall.
as administrative 2) Measure the individual elements and compare the
regulation). existing elements to the proposed windows or doors.
Replacement windows This must include glass size (width and height),
and/or doors should muntins, casing (width and depth), sash face, profiles,
replicate the material, inset, pitch of sill, thickness of sill, and how the
design and dimensions window or door meets the existing wall.
of the original windows The revised guidelines aim to provide a side by side
and/or doors as closely comparison of the existing and the proposed window
as possible. or door to assure the replacement window will not
significantly change the historic character, type or style
of the house.
Development of Revised guidelines includes new section 3.7.4
guidelines for assessing Retrofitting Historic Windows, which acknowledges
the appropriateness of that historic glass in windows maybe of higher
retrofitting historic sash importance on the primary elevation of a designated
with thermal pane building and discourages thermal-pane retrofits on
glass. This item was not this face of a building when intact historic glass is
part of City Council extant. Retrofit of single-pane sash with thermal-pane
direction, but has glass on secondary and tertiary elevations usually
become an issue over the appropriate. Retrofit of multi-pane windows with
past year. thermal pane glass is usually inappropriate.
Specifications are given to ensure that window
retrofits closely match appearance of unimproved sash
and frames.
In establishing guidelines to assess both "historic character and value' and
"location' of doors and windows, the matrix (below) was established to provide
guidance as to when "replacement "or "retrofit" of historic windows or doors
may or may not be appropriate as follows:
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Very Historically Non-Historic
Historically Important
Important
k -
Primary Elevation ~ Repair .Repair ° - o -
Secondary Repair" Reviewed case ° - n .
Elevation by case . -
. e~ ~ ~
Tertiary Repair ~ - m . ' ° ~ - E
Elevation ® • • * -
.
Revisions to the General Design Guidelines:
8.2 Energy Efficiency & 8.3 Mechanical and Utility Facilities
Encourage solar Guidelines revised to include current information
collectors and skylights related goal of meeting Kyoto Protocol and
to be placed in compatibility of historic preservation and
inconspicuous environmental sustainability, energy audits, and
locations, however, as flexibility regarding location of solar collectors and
new solar collector installation of historic shutter when there is historic
technologies emerge precedent-
with less noticeable
collectors, more
flexibility should be
given to solar collector
placement.
Allow shutters where
there is historic
precedent.
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r;,~~~..~ Ifs ~y2 ~ 8
Item 1(b.)
9.0 Definitions
Definitions to support Added definitions in revised guidelines include, very
proposed changes. historically important window or-door, historically
important window or door, non-historic window or
door, primary elevation, window retrofit, primary
elevation, secondary elevation, tertiary elevation,
retrofit, and window or door deterioration: class I,
class II, class III, class IV.
Items 2 through 4 of the City Council's policy direction call for historic
preservation and environmental affairs staff as well as the Landmarks Board and
the Environmental Advisory Board to take steps educate the public as to issues
surrounding historic preservation and environmental sustainability as follows:
Items 2-4
City Council Direction Steps Taken
Item 2. Continue work Brochure entitled "Making Your Historic Building
on a brochure that More Energy Efficient" by staff and reviewed by the
outlines techniques to Landmarks Board and Environmental Advisory
make historic buildings Board. Accompanying website currently under
more energy-efficient. construction.
Item 3. Evaluate Revisions to Green Points program provides for points
options for the city to when historic windows and doors on designated
take more proactive buildings are rehabilitated, sealed, and for installation
measures to improve of appropriate storm systems. Historic Preservation
the energy efficiency of program and Environmental Affairs promoting
historic buildings, and subsidized energy audits for historic buildings.
discourage the
demolition. of historic
buildings and removal
of historic building
materials.
Item 4. Work with the Revisions to Design Guidelines (see above}. Revised
EAB and LPAB to Green Points provides for points when historic
revise the Historic windows and doors on designated buildings are
Preservation and Green rehabilitated, sealed, and for installation of
Points guidelines, appropriate storm systems. City staff is working with
adding Green Points Historic Boulder to provide public information about
or: rehabilitatn techni ues for makin historic windows more ener
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historic houses, efficient.
instaliing storm
windows and doors to
historic windows and
doors, weather
stripping and sealing of
leaky historic windows
and doors.
Together these steps represent significant progress toward achieving the goals of
the policy direction given by the City Council in January of 2007. Given the
advances in energy efficiency technology and the dynamic nature of historic
preservation philosophy and practice, staff recommends that issues related to the
city's environmental sustainability and historic preservation programs be
reviewed by the City Council biennially.
NEXT STEPS:
November 13, 2007: Update City Council on implementation of the
HIPESIP including adoption of Administrative
Regulations/Design Guidelines regarding historic
windows and doors by the Landmarks Preservation
Advisory Board.
ATTACHMENTS:
A: Proposed revisions to General Design Guidelines, Sections 3.7 Windows,
3.8 Doors, 9 Definitions.
B. January 16~, 2007 Council Memo
C. Stakeholder Comment: Lisa Egger, AIA; Larry Kinney, Synergistic
Building Technologies; Eric Doub, Ecofutures Building, Inc.; Lynne
Bingham, Phoenix Window Restoration; Joe Saldibar, historic preservation
architect, Colorado Historical Society.
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-
~~~~x~~s
Attachment A
GENERAL DESIGN GUIDELINES
FOR BOULDER'S HISTORIC DISTRICTS AND INDIVIDUAL LANDMARKS
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CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD NOVEMBER 2007
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5. ADDITIONS TO NON-HISTORIC STRUCTURES 45 y:~ °M. =~i ~ K `
6. NEW PRIMARY STRUCTURES ' 47 ~ '
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6.1 Distinction from Historic Structures 48 , s ~ -;r
6.2 Site and Setting 48 h -~"E` a'. .
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6.3 Mass and Scale 49 , " , - s
6.4 Materials 50 ~
6.5 Key Building Elements 50 ~ ~ ,
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7. GARAGES & OTHER ACCESSORY STRUCTURES 53 ~ ~ ' - ~f... -
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7.1 Existing Historic Accessory Structures 54 K _
7.2 New Accessory Structures 54
8. MISCELLANEOUS 57
8.1 Paint and Paint Colors 58
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8.2 Energy Efficiency 59
8.3 Mechanical and Utility Facilities 59 ~~t
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8.4 Signs 60
8.5 Lighting 61 - -
8.6 Artwork 61 z < '
8.7 Public Improvements 62 ° ~ ~ >~A, ~ ~
8.8 Americans with Disabilities Act 62 ~ -
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9. DEFINITIONS 65
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ACKNOWLEDGEMENTS
Landmarks Preservation Advisory Board
(I 998 - 2003
Kathy Arnold Tim Plass
Leslie Durgin Lisa Podmajersk
Lisa Egger Sharon Rosall
Michael Holleran Leland Rucker
Nancy Kornblum Rory Salance
Leonard May Kent Stutsman
Kirk Watson
Consultant
Nancy Lyons, Preservation Partnership
City of Boulder Staff
A number of current and former city employees contributed to ,
this project, including Ruth McHeyser, Deon Wolfenbarger,
Neil Holthouser, Lara Ramsey, a~Bohdy Hedgcock
Cameron, Chris Meschuk and Tames Hewat.
Photos and Graphics
Bohdy Hedgcock, Robin Madel & Matt Russell -City of Boulder
Winter & Company
Carnegie Branch Library for Local History
Denver Public Library -Western History Collection
Funding
This project was sponsored by the City of Boulder Landmarks
Advisory Board and has been financed in part with Federal
funds from the National Historic Preservation Act,
administered by the National Park Service, U.S. Department of
the Interior and for the Colorado Historical Society. However,
the contents and opinions do not necessarily reflect the views or
policies of the U.S. Department of the Interior or the Society, nor
does the mention of trade names or commercial products
constitute an endorsement or recommendation by the
Department of the Interior or the Society.
This program receives Federal funds from the National Park
Service. Regulations of the U.S. Department of the Interior
strictly prohibit unlawful discrimination in departmental
Federally assisted programs on the basis of race, color, national
origin, age or handicap. Any person who believes he or she has
been discrirnuZated against in any program, activity, or facility
operated by a recipient of Federal assistance should write to:
Director, Equal Opportunity Program, U.S. Department of the
Interior, 1849 C Street, N.W., Washington, D.C. 20240.
CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD ~ ~-l
CONTENTS
s
tj _ ~
$ ~ r - I . INTRODUCTION 5
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- _ ,
' 7 ~ ~ ~d ~ ~ ; 1.1 Historic Preservation Program 6
- ~ S 'S .f
- 1.2 Purpose of the Design Guidelines 8
Y. Y:.
~ • 1.3 A History of Boulder 10
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3 ~ 1.4 Architectural Styles In Boulder 13
~r 1.5 Review Process 18
r
2. SITE DESIGN 2I
~ ° ~ ~ " .'m 2.1 Building Alignment, Orientation, and Spacing 22
~
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_ ~ ~ - x ~ , i 3 2.2 Streetscape and Landscaping 23
~a rt ' ~
~ : - 2.3 Alleys 24
a „ f ~ ~tl* r
2.4 Parking, Driveways 25
I.. F ~ L'
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~ 2.5 Sidewalks 26
F
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2.6 Fences 27
A~ ~ ~ ar= ~ " 3. ALTERATIONS 29
~;~i~ x
ts'.r - 3.1 Roofs, Skylights, and Solar Panels 30
'f L - , t w
~a ~ 3.2 Roof Decks and Balconies 31
. , ~
3.3 Decks 32
' f
Fp•~F
t ~ ~ < : ~ K ~ 3.4 Porches 33
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3.5 Dormers 34
,
3.6 Exterior Materials: Walls, Siding, and Masonry 35
x _
1 3.7 Windows, Storm Windows, and Shutters 35
- r. -
v ~ 4 ~ 3.8 Doors and Storm Doors 3S
~ 4. ADDITIONS TO HISTORIC STRUCTURES 39
-
~ 4.1 Protection of Historic Structures and Sites 41
~ ~ < n -
t ~..~•~.t - 4.2 Distinction from Historic Structures 41
4.3 Compatibility with Historic Structures 42
E
x 4.4 Compatibility with Historic Site and Setting 42
4.5 Key Building Elements 43
INTRODUCTION
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CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD
I. INTRODUCTION
1.1 Historic Preservation in Boulder
The early 1970's saw an increase in the demolition of existing
buildings with no thought as to their historical or architectural
value to Boulder's history. Among those demolished was
Central School, the first school to have a graduating class in the
Colorado Territory. Today, at the corner of Walnut and 15~ is a
plaque, embedded in rock, commemorating the school. Out of
the school's destruction rose the demand for a legal mechanism
for evaluating historic sites. In 1974, the Boulder Landmarks
Ordinance was passed. The ordinance sets out the procedures
for designation, design review, and the appointment and
powers of the Landmarks Preservation Advisory Board (LPAB).
The purpose of the historic preservation program as stated in
the Ordinance is as follows:
Over ~-140 properties (a) The purpose of this chapter is to promote the public health,
safety, and welfare by protecting, enhancing, and perpetuating
have been designated as buildings, sites, and areas of the city reminiscent of past eras,
local landmarks, along with events, and persons important in local, state, or national
these historic districts: history or providing significant examples of architectural
styles of the past. It is also the purpose of this chapter to
Floral Park 1977 develop and maintain appropriate settings and environments
Chautauqua 1978 for such buildings, sites, and areas to enhance property values,
Mapleton 1982 stabilize neighborhoods, promote tourist trade and interest,
West Pearl 1994 and foster knowledge of the city's living heritage.
Chamberlain 1995 (b) The city council does not intend by this chapter to preserve
Downtown 1999 every old building in the city but instead to draw a reasonable
Grandview 2000 balance between private property rights and the public interest
Hillside 2001 in preserving the city's cultural, historic, and architectural
Highland Lawn 2005 heritage by ensuring that demolition of buildings and
University Place 2006 structures important to that heritage will be carefully weighed
~h with other alternatives and that alterations to such buildings
16 Street 2006 and structures and new construction will respect the character
of each such setting, not by imitating surrounding structures,
A complete listing of but by being compatible with them.
individual landmarks is
available on the city's Landmarks Preservation Advisory Board Mission:
website: To protect, enhance, and perpetuate buildings, sites, and areas of the
city reminiscent of past eras, events, and persons important in local,
state or national history or provide significant examples of architectural
styles of the past..... also to develop and maintair? appropriate
settings and environments for such buildings, sites, and areas to
boulderhistoric
presenration.net enhance property values, stabilize neighborhoods, promote tourist
trade and interest, and foster knowledge of the city's living heritage.
b GENERAL DESIGN GUIDELINES l
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CITY OF BOULDER LOCAL HISTORIC DISTRICTS (20070
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Chautauqua j Floral Park
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, Mapleton
1.2 Purpose of the Design Guidelines
- _ _ _ The intent of the design review process is to ensure that
_ proposed alterations of Landmark properties will not adversely
affect or destroy their historic character or architectural integrity
a- and that all changes are consistent with the spirit and purpose
- = of the Landmark Preservation Ordinance. The Landmarks
_ ~_~.,.._4
f ° Board adopted the Secretart~ of the Interior's Standards for
~ _ Rehabilitation as the basis for guidance on rehabilitation design
~ ~ - - for historic properties.' These guidelines expand those
---°~T j Standards and bring focus to Boulder's own historic context and
_ ~ _
- resources. The guidelines are intended to be used as an aid to
_ ~~ropriate design and not as a checklist of items for
_ _ _ ~T
1 compliance.
The purpose of the design guidelines is to facilitate both the
application and approval of alterations proposed for design
review by
1) providing the owners of historic properties some
- assistance in making decisions about maintenance and
- ~ - - improvements, and
- _ ; 2) providing the Landmarks Board with a framework for
evaluation of proposed improvements.
i_~ - -
_ ~ _ = The guidelines reflect the Landmarks Board's philosophy that
- _ - _ _ - underlies all its decisions: to encourage the preservation and
_ " careful treatment of the city's historically significant resources,
~ ~ while recognizing the need for continuing adaptation and
improvements to these resources.
- -~1
, _ ~ _ - The General Desi~~ Guidelines serve as the guiding document for
_ present and future residential historic districts and individual
Survey sheets like these document landmarks, supplemented by district-specific guidelines where
Boulders hiscoric resources. those have been adopted. The district-specific guidelines are
available from the Planning Department. Call a Preservation
Planner at (303) 441-3~A-1880 for more information. For
individually landmarked commercial btuldings and for the
Downtown Historic District, refer to the Downtown Design
Guidelines.
Before you begin to formulate plans for any changes to your
building, find out whether it is considered individually significant,
contributing, contributing-restorable, ornon-contributing. This
information will help you to better understand these guidelines as
'Adopted by the Landmarks Board as administrative regulations, 11/7/1990
8 GENERAL DESIGN GUIDELI
they apply to your btulding. You can find this information on
historic surveys completed for all buildings in historic districts and A searchable database of
far landmark stntctures. Surveys are available from the Planning some information from
Department at 1739 Broadway and at the Carnegie Branch Library the survey sheets, along
for Local History, 1125 Pine Street, Boulder. It should be noted with recent photos (2002
that the stahis of buildings can change over time, and not all - 2003) of individual
surveys are up to date. The determination of contributing or non- landmarks and buildings
contributing status is ultimately made by the Landmarks Board in within Boulder's local
consultation with staff. historic districts is now
available on the city's
The Secretary of the Interior's Standards for Rehabilitation website. You may also
retrieve information by
I. A property shall be used for its historic purpose or be placed in a new use
that requires minimal change to the defining characteristics of the building selecting properties from
and its site and environment. a map of Boulder's historic
properties.
2. The historic character of a property shall be retained and preserved. The
removal of historic materials or alteration of features and spaces that www
characterize a property shall be avoided.
3. Each property shall be recognized as a physical record of its time, place, and #sister+~h~lboulderhistoricoreservati
use. Changes that create a false sense of historical development, such as on.net
adding conjectural features or architectural elements from other buildings,
shall not be undertaken.
4. Most properties change over time; those changes that have acquired historic
significance in their own right shall be retained and preserved.
5. Distinctive features, finishes, and construction techniques or examples of
craftsmanship that characterize a property shall be preserved.
6. Deteriorated historic features shall be repaired rather than replaced. Where
the severity of deterioration requires replacement of a distinctive feature, the
new feature shall match the old in design, color, texture, and other visual
qualities and, where possible, materials. Replacement of missing features shall
be substantiated by documentary, physical, or pictorial evidence.
7. Chemical or physical treatments, such as sandblasting, that cause damage to
historic materials shall not be used. The surface cleaning of structures, if
appropriate, shall be undertaken using the gentlest means possible.
8. Significant archeological resources affected by a project shall be protected
and preserved. If such resources must be disturbed, mitigation measures shall
be undertaken.
9. New additions, exterior alterations, or related new construction shall not
destroy historic materials that characterize the property. The new work shall
be differentiated from the old and shall be compatible with the massing, size,
scale, and architectural features to protect the historic integrity of the
property and its environment.
10. New additions and adjacent or related new construction shall be
undertaken in such a manner that if removed in the future, the essential form
and integrity of the historic property and iu environment would be
unimpaired.
- - . ^s:i?~f IlvtN f~~_~ I'C.Jv 11
The definitions below help to explain the different categories of
significance:
¦ Local Landmark Buildings:
Those buildings that are officially designated as
city of Boulder local landmarks. These buildings
have a special character and historical,
architectural, or aesthetic interest or value in
Boulder's local history.
¦ Individually Significant Buildings:
Those buildings that are considered individually
eligible for the National Register of Historic
Places or for local landmark designation.
¦ Contributing Buildings:
Those buildings built during the district's period
of significance that exist in comparatively
original condition, or that have been
appropriately restored, and clearly contribute to
the historic significance of the district. Such
buildings may have compatible additions.
¦ Contributing-Restorable Buildings:
Those buildings built during the district's period
of significance that have original material that
has been covered, or buildings that have
experienced some alteration, but that still convey
some sense of history. These buildings would
more strongly contribute, however, if they were
restored. Such buildings may have less
compatible additions.
¦ Non-Contributing Buildings:
Those buildings built during the district's period
of significance that have been altered to such an
extent that historic information is not
interpretable and restoration is not possible. This
includes buildings erected outside the period of
significance that are not individually significant.
¦ Significant Newer Buildings:
Those buildings that have not yet achieved
historic significance but have achieved
architectural significance as excellent examples of
their period.
• GENERAL DESI LINES
1.3 A History of Boulder
The Boulder valley was first the home of American Indians,
primarily the Southern Arapaho tribe that maintained a village
near Haystack Mountain. Utes, Cheyennes, Comanches, and
Sioux were occasional visitors to the area.
Gold seekers established the first non-native settlement in
Boulder County on October 17,1858 at Red Rocks near the
entrance to Boulder Canyon. Less than a year later, on February
10, 1859, the Boulder City Town Company was organized by
A.A. Brookfield, forty-four lots were laid out at a purchase price
of $1,000 each; a price that was later lowered in order to attract
more residents
Part of the Nebraska Territory until February 29,
1861, when the U.S. Congress created the Territory of ; ~ ~ ; 7 jf~~~F, _
Colorado, Boulder Ci rew slowl It develo ed as ~ : ~r~'"
a supply base for miners going into the mountains in
search of gold and silver. Boulder City residents
provided miners with equipment, agricultural _
products, housing and transport services, and ~
gambling and drinking establishments. : • a e4'~4 y
~ ` ti oy-, ~ J. ' .
Competition among Boulder County settlements for "°b'=`~ - - ~
. _ _
new residents and businesses was intense. Asa ~ -
.
mining supply town, Boulder residents were more ` _ _
settled than in the mining camps. Economic stability Bird's Eye View of Boulder City, 1876
was a necessity and residents encouraged the establishment of Carnegie Branch library for Locof History,
railroad service, hospital and school buildings, and a stable town Boulder Historical Society Collection
government.
Boulder's first schoolhouse was built in 1860 at the southwest
comer of Walnut and 15th Street, the first in the territory. Also in
1860 a group of Boulder residents began lobbying to have the
University located in Boulder. By 1874 Boulder had won the
designation, secured a donated 44.9-acre site and raised $15,000
to match a similar grant by the state legislature. Construction of
Old Main signaled the opening of the University with
classrooms, offices, an auditorium and the President's living
quarters all located there.
Transportation was improved in 1873 with railroad service
coming to Boulder. Gradually tracks were built to provide
service to Golden and Denver and to the mining camps to the
west. In 1890, the railroad depot was constructed on Water Street
(now Canyon Boulevard) and 14th Street.
INTRODUCTION - w
i
City government was formalized in November 1871, when the
town of Boulder was incorporated. Designation of Boulder as the
county seat occurred in 1867 and led to the construction of the
first courthouse at its present site in 1883. It burned to the
ground in 1932 and was replaced by the current courthouse in
1934.
Amenities and health services were developed, even in periods of
little growth. The first Post Office was established in 1860; a
hospital was built in 1873; 1874 saw the arrival of the telegraph, a
water system and the first bank.
The initial residential area was located in what is now downtown
and in some parts of the Goss/Grove, Whittier and Mapleton Hill
neighborhoods. As commercial expansion took over downtown
housing, the surrounding neighborhoods remained primarily
residential areas. At the turn of the century growth of the
University led to the development of University Hill. One mark
of elegance for residents was the flagstone sidewalks, first
installed during the 1880's.
The first private school in Boulder, Mt. St. Gertrude
Academy, was opened in 1892. Boulder, by then
~ ~ x,~~ accessible to visitors by railroad, was known as a
~
` ~,b=' community with a prosperous economy, a
' a,~ comprehensive educational system, and well-
~t ~ - ~
- ` A` a maintained residential neighborhoods. It was no
~ ` ° ; ~ ~ ~ ~ ~ ~ t,: - ~ wonder that the railroad recommended Boulder as a
~ ' ~ site fora Chautauqua in 1897. Boulder residents
~ ~..n ~ passed a bond issue to buy the land, and the now
` ~
g ' ~ ~'~3-~ ~ ~ ~ Y familiar Chautauqua Park is listed both on the
~ National Register and as a locally designated
_ landmark.
View of the Flatirons and Boulder, 1920
Denver Public Library -Western History By 1905 the economy was faltering and Boulder counted heavily
Collection on tourism to boost its fortunes; however, Boulder had no first
class hotel to attract summer visitors and group meetings. By
1906, a subscription drive had raised money to begin
construction. The first event at the new Hotel Boulderado was a
reception for Boulderites on December 30,1908. The hotel opened
to the public for business on January 1, 1909.
Tourism continued to dominate the Boulder economy for the
next forty years. Each summer shopkeepers, transport firms, and
lodging managers eagerly awaited the influx of Chautauqua
residents (primarily from Texas) and other visitors. By World
' GENERAL DESIGN GUIDELI ES Z
pia L"_ C.i,~{i
War II, when tourism declined, the University had unknowingly
provided another opporhtnity for growth. With the location of
the U.S. Navy's Japanese language school at CU yotmg men and
women from around the country became acquainted with the
city and liked it.
Following World War II many of these trainees returned as
students, professionals and business people, joining veterans
attending the University on the G.I. Bill. Boulder's population
had not increased significantly since the 1920's. The 1920 census
showed 11,006 residents while the 1940 count was 12,958. After
the first influx of new residents in the late 1940's, the count
soared to 20,000 in 1950.
New residents meant both new opportunities and - _ -
new challenges. Although jobs were needed, - ~ '
townspeople wanted to preserve the beautiful natural
setting and amenities developed over the years. By - . , ,
1950, Boulder leaders were actively recruiting new y ~ .~~Y~ -
"clean" industry and improved transportation, ~ _ s..~ ~ -
securing a new highway, the Boulder-Denver ~
Tttmpike; and the National Bureau of Standards in _ ~
1952. Other research and development industries ,,,.-~,.~.K~,
soon followed. ~ ~ ~
The housing shortage and need for additional ~ ~ ~
business and public buildings attracted young and ~ =•a-~:~-~
talented architects. New subdivisions were planned ~ ~
~ r ~r
including the Highland Park-Martin Acres ~ ~ f' f ~ `
neighborhood located on the historic Martin Farm ~ ~ `
and the North Boulder developments from Balsam ~:~~y'~i~~~~_ K ~ ~ J
4 y,~. K "m.µ.1 . ~ .~GZ~
north, originally part of the Tyler Farm. New ~ ~
neighborhoods brought the city's first two shopping ; °~3. „ ~ _
centers, North Broadway and Basemar- With the , ~3~ °
~ ~ t `
r"
completed turnpike to downtown Denver Boulder f ~ ~ r
continued to ex and. From 1950 to 1972 the ~~~~,.~`~''~-~"J'~~ ~ k=
p - f
population grew from 20,000 t0 72,000. Boulder-Denver Turnpike, 1952
Carnegie Bronch Library for Locol History,
With the purchase of thousands of acres of open space beginning Boulder Historical Society Collection
in 1967, the adoption of the Boulder Valley Comprehensive Plan
in 1970, passage of the building height restriction ordinance in
1972, and the residential growth management ordinance in 1977,
Boulder began a period of infill and reuse of its past architectural
development that continues to the present. The Historic
Preservation Code was passed in September 1974. The
ordinance is instrumental in preserving significant portions of
ottr past while encouraging rehabilitation of historic btildings.
INTRODUCTION n^'S fi G n°r,. rc
1.4 Architectural Styles in Boulder
Understanding the stylistic trends, the design intent, and the
traditional use of building materials is important to the
evaluation of a structure's historic integrity and consequently to
rehabilitation design. While a large portion of Boulder's historic
residential properties are properly identified as "vernacular",
they also include examples of a broad range of architectural
styles that reflect the evolution of Colorado architecture dating
from the 1880's. The following styles are found in Boulder. The
descriptions are excerpted from a 1983 publication of the
Colorado Historical Society, A Guide to Colorado Architecture.
- - Vernacular Wood Frame (late 1860-present)
i By far the most common style of architecture, Vernacular Wood
' - : Frame structures have been built throughout Colorado since
. - 1860. The Vernacular is an indigenous style generally
~ constructed with locally available materials according to
traditional building practice. They are simple in form and detail
- i and generally void of ornamentation. These simple, modest
ti,,
` ~ ` ~ homes are divided into four types according to floor plan and
roof shape: the Gabled "L", the Front Gable, the Hipped Gable, ~
Vernacular Wood Frame
Greenman House and the Side Gable. These buildings are wood frame
Mapleton Avenue construction and are usually sided with clapboard or wood
shingles or a combination of the two.
~ . :Vernacular Masonry (late 1860-present)
~ ,
z'~~~ ~ ~ Vernacular Masonry is another very common form of
~.z ~.rY rl~ `Y ! architecture found all over Colorado and dates from the late
j 1860's. Although not as common as Vernacular Wood
e structures, these unpretentious building are numerous enough
to warrant a separate category. They are generally composed of
- brick, stone, or concrete block and are similar in massing to
Vernacular Masonry their wood counterparts. As with Vernacular Wood structures,
John Day House these buildings are simple in detail and are designated
19`" Street according to roof shape and floor plan into four categories: the
Gabled "L", the Front Gable, the Hipped Box, and the Side
y
Gable.
yes;"'' ~ u r
~,:yY~ rl ::.~_t ~ Italianate (I 870- 19 10)
,A I Like many Victorian styles, the Italianate emphasized vertical
~ j~'" proportions and richly decorative detailing. It was found on
~ I residential, commercial, and institutional structures throughout
A
may. Colorado from about 1870 up until the turn of the century and
S.r 'Yfy Y~ p-~ji+u~~r sc'R".~hy^.~
is either wood or masonry construction. The Italianate style is
Italianate characterized by a low pitched, hip roof, wide overhangs,
Austin House
Pine Street bracketed cornice, a variety of fenestration (usually very tall,
GENERAL DESIGN GUIDELIN/E~S a
thin, double-hung, one-over-one winnows), molded window k
surrounds, and occasionally a cupola or balustraded balcony.
Simple Italianate structures have a hipped roof, bracketed ~ ~ ^ ~ -
eaves, and molded surrounds. Amore elaborate or High Style
example may feature arcaded porches, corner quoins, towers, _
Fes:
and ornate detailing. ; •
~.qy
.M,.
Second Empire (I 870- 19 10) _
The Second Empire style is most easily identified by the use of a Second Empire
Mansard roof form, adouble-pitched roof with a steep lower Chauncey Stokes House
slope. The roof is usually pierced with dormer windows Pine Street
allowing light to this second or third floor. Decorative elements
on the facades include triangular pediments over windows and
porches and pilasters and columns at building comers.
Queen Anne (I 880- 19 10) , ;
Queen Anne is perhaps the most ornate style of the Victorian ~
Period evident in Colorado, and was popular between 1880 and _ .f
1910. The style varies from highly decorative commercial ~ -
examples to more restrained version found in many residential ' ~l ~ ~ ~
neighborhoods.
General characteristics include a vertical orientation I ~ -s~ 'i~
e~c xl~ ~ @iEl~
L_ ~Y' 1 S~liSil
asymmetrical massing, corner towers and bays, prominent
decorative orches, ro~ectin ables, and contrastin materials. Queen Anne
P P 1 g g g McAllister House
First stories are often brick or stone with wood frame upper Pine Street
stories finished with wood shingles or clapboards. Roof forms
are often complex with gabled or hip dormers and tower
elements. Wide front orwrap-around porches are typically
found on front and side elevations with elaborate trim and
turned posts. The degree of ornamentation usually ,.:,r.^,:,,-:
distinguishes the High Style from the vernacular.
_ ~
Ornamentation is emphasized on a High Style Queen Anne ,
through the use of scalloped and painted shingles in the gable 4~4=._
ends, and decorative bargeboards, sunburst detailing, and
1
turned spindles on porches and balconies. The corner tower is ~
prominent, but not universally present.
The Vernacular g y ~ ~ ~ .r
Queen Anne is enerall less ornate, but
usually features the shingled gables, asymmetrical massing and t
some decorative detailing. The vernacular examples have
enough decoration to distinguish them from the categories that F,;~:.,,..
are strictly vernacular.
Queen Anne
Temple-Bowron House
Pine Street
INTRODUCTION ~ ~r
Edwardian Vernacular (1900-1920)
x
Edwardian Vernacular structures are basically Post-Victorian
~ ~ residences similar to the Queen Anne style inform and
massing, but lacking ornamentation. Sometimes called
~ ~ "Princess Anne," these buildings feature mold-gabled roofs,
r
asymmetrical massing, simple surfaces, and occasionally wrap-
~ _ ~ around porches, short towers, and some classical details.
Edwardian Vernacular Terrace (I 880- 1920)
Lamb House The Terr~ue is considered to be somewhat unique in Colorado
Spruce Street and dates from the late 1880's through 1920. These structures
are basically one or two-story brick building with a flat roof and
corbelled cornice. The style is evident in a few single-family
- ;homes, but most common as duplexes or larger multi-family
homes. ':any have individual porches at each entrance. While
_ the mor;', common cornice treatment is brick corbelling,
- - occasionally a separate cornice with brackets or parapets at ±he
~ ~ I roofline are evident. Stylistic elements such as Richardsoruan
I'~, arches or Italianate bracketed cornices are used occasionally,
but the basic flat-roofed. Rectangular form predominates.
Terrace
Johnson-Betasso Terrace Foursquare (I 900- 1930)
Pearl Street One of the most commonly found styles in Colorado after 1900.,
the Foursquare is easily recognized by its square plan ar..l
overall sirilplicity. The majority of these homes were built
~;j ~ during the first three decades of the 20~ century. The typical
Foursquare is a two-story, hipped roof structure with central
y~~.. ! front dormer, minimal decoration, broad overhan~in eaves
, ~ i ~ ~ ti ~ b g
, with brackets or modillions, classical frieze with dentils, and a
` i porch with hipped roof supported bu simple, Doric columns or
" ~ ~ square posts. Occasionally, a Foursquare will feature a shaped
o~ gable or will be considerably larger with more elaborate
ornamentation, but, in each case, the basic square plan is
Foursquare predominant.
Mayan-Pickett House
Highland Avenue
Classic Cottage (19 10- 1930)
The Classic Cottage is basically a one-story version of the
Foursquare. It features an elongated hipped roof with central front
dormer, a front porch with thick porch posts or round, simplified
Doric columns supporting the porch roof. Popular between 1910
. - ~ ~ and 1930, the style was most commonly used in residential
~n.._, -
I architecture, although occasionally it was used for schoolhouses,
_ I train depots, or small institutional buildings. Building materials
were almost always masonry, particularly brick, with a few rare
:sW~~~~ ' frame examples. Ornamentation is generally limited to window
Classic Cottage r 1 surrounds and flared eaves on the dormer.
Mapleton Avenue
GENERAL DESIGN,;6UIQELI r` .,n
Colonial Revival (I 900- 1930)
Classical or Colonial Revival buildings constructed in the early ~
twentieth century generally have classical detailing. Buildings ~
~ -
in this style vary widely in size, may be of wood or masonry ~f..
construction, and have details such as pediments, dentiled ~i~ ~ ~ ,,pia
cornices and multi-paned windows. Front doors are usually ~ ~"t"'°""
accented with pediments or fanlights and porches are typically ~ ~ s ;
small with slender columns. Roof forms can be hipped or
gabled, but are usually simple in massing. colonial Revival
Henrietta Somers House
Mission (I 900- 1930) Baseline Road
The Mission style is most easily identified by the curvilinear
shaped gable and simplicity of form. Also characteristic is a
stucco or plaster finish, arcades, file roof, and, occasionally, ~ ~ : _ r.~,; } ,
arched windows. There is usually a small round window or ~ ~ ~ ~ ~ k
A ~ ~ r°
round ornament located in the center of the shaped gable. ~
Towers and iron balconies are evident on larger buildings. ` ~
nZ
:aid. '
Tudor Revival (I 9 10- 1930) ` '
The most dominant features of the Tudor Revival style are the ~ G~ ~
half-timbering that covers the upper story, and the very steeply Mission
pitched roof. The exterior is textured, using brick, stone, or Wahlstrom MissionlTerrace
stucco, and, together with the timbering, give the house a 19`h Street
picturesque composition. Constructed in Colorado during the
1910s and 1920s, these homes also featured gabled or hipped
roofs covered with tile, slate, or shake shingles, and decorated
chimney detailing. Windows are generally mullioned ~ ' '
casements, with an occasional bay window.
~
Mediterranean (I 920- 1930) ' ~
- .
The key to distinguishing the Mediterranean style is the file roof ~ ;r--_..~'~ +
j~~V&~
and restrained ornamentation (as opposed to the elaborate i ,
details on a Spanish Colonial Revival structure). Built in - - - _ - '
Colorado during the 1920's, these struch>res are generally Tudor Revival
Ekeley House
stucco or brick, often painted white to contrast the brightly I l street
colored roof tiles. Roofs are low-pitched gable or flat with a
parapet on smaller homes; they are low pitched hipped on some
larger homes. Another characteristic feahire is the extension of
aside or front wall to form an arcaded entrance or porch.
Windows are sometimes casements, framed by wooden or _ ,
~~rought iron grills or small second story balconies. ~ ` ~
The Mediterranean style was used for churches, schools, and
~.r - ~ ~
residences, both on a grand scale and on more modest homes. A; _ ~
The heavy file roof is generally the dominant characteristic - `
Mediterranean
David H. Holmes House
I I Street
INTRODUCTION h~'^!~~a ~E~i`:~ - ~ rfFv ~f_
• I~
_ Bungalow (I 920- 1940)
~ ' - The Bungalow style incorporates a wide range of styles from
~ Craftsman to Prairie and Mission style buildings. Often
~ ~ Rt categorized as modest one or one and one half-story buildings,
defining features include large covered porches, low
f~
~ overhanging roof forms and large scale building elements.
Porch columns tend to be squared and tapered and often sit on
. ~ ~ pedestals. Bungalows can be wood or masonry, but share these
Bungalow common elements.
6th Street
- - Modern (1920 -present)
~ { r~" Architecture associated with the Modern movement is
_ ~ I! identified by an emphasis on design that was clearly of the
Machine Age, with standardization of parts, absence of non-
' functional decoration, and structural "honesty" as hallmarks.
~I Flat roofs and smooth wall surfaces were favored. Both the
Modernistic style (1920 - 40) and the International style (1925 -
~ - present) are products of this more austere modernism.
Modern
Thornton House
13`h Street
GENERAL DESIGN GUIDELINES
1.5 Review Process Section a-A9-+I 13-18 of
the Boulder Revised Code
What is Subject to Review? establishes criteria for the
The Boulder Revised Code's Historic Preservation Ordinance approval of Landmark
(~89-X311-18, B.R.C., 1981) outlines the process and criteria for
reviewing changes to individual landmarks and buildings in Alteration Certificates:
historic districts. Any alteration to the exterior of a building or
site in a locall desi ated historic district or on a Landmark I.The proposed work
y ~ preserves, enhances, or
site requires a Landmark Alteration Certificate. Items such as restores and does not
changing the paint color, major landscaping projects and the damage or destroy the
addition of storm windows do not require a building permit, exterior architectural
but they do require a Landmark Alteration Certificate. features of the landmark or
the subject property within
What is the Process for Review? an historic district;
There are three levels of review. 2. The proposed work does not
adversely affect the special
¦ Staff Level Review: The following alterations can usually be character or special historical,
reviewed within a few days by calling a city Preservation architectural, or aesthetic
Planner at 441-~A1880: re-roofing, paint, landscaping, and interest or value of the
rear or side yard fences lower than 5 feet in height with a landmark and its site or the
minimum of 1" spacing between the pickets. For projects in district;
downtown, staff may also review signs, awnings and 3.The architectural style,
railings. If such a proposal clearly meets the criteria arrangement, texture, color,
outlined by the preservation code (see sidebar), a arrangement of color, and
Preservation Planner will issue a Landmark Alteration materials used on existing and
Certificate, and you can commence your project. (You will proposed structures are
also need a fence permit for fences and a building permit for compatible with the
character of the existing
re-roofing prior to beginning any work, however). landmark and its site or the
historic district; and
¦ Landmarks Design Review Committee: All other projects
will be reviewed by the Landmarks Design Review 4. With respect to a proposal to
Committee, which meets weekly and consists of two demolish a building in an
members of the Landmarks Board and one member of the historic district, the proposed
city Planning Department (a city Preservation Planner). Call new construction to replace
the building meets
a Preservation Planner to schedule your review with the requirements 2 and 3 above.
Committee. The meetings are relatively informal, and you
are encouraged to bring your proposal early in the design The complete historic
process for a conceptual review. As the project becomes preservation ordinance is
finalized, the Committee determines whether it meets the available online at:
guidelines set forth in this document and in the Boulder
1 fistoric Preservation Code. If it does, the Committee will wv~ Ei-bealde~~-ds><
issue an Alteration Certificate, and you can commence with
your project after getting the necessary permits. If the vote ','~bouldercolorado.gov
of the Committee is divided, the application goes forward
for review by the five-member Landmarks Board at a public
hearing unless you choose to withdraw the application for
revision and resubmittal. ~ Q~
AQItId9 ~11~
` -PiiQBI~--?
INTRODUCTION
¦ Landmarks Board Public Hearing: In addition to projects
Incentives for referred to the Board by the Design Review Committee, the
Landmarking full Landmarks Board reviews all demolition and new
construction applications. Sheds under 60 square feet in
As a way to encourage size and one-story single car garages under 340 square feet
landmark designation of are exceptions, and can be reviewed by the Design Review
the city's eligible historic Committee. Landmarks Board public hearings are held
resources, the city and monthly, and agendas are published in the newspaper 10
state offer a variety of days in advance. Decisions are based on the majority vote
incentives to property of the five-member Board and standards in the Code.
owners including:
Call Up by City Council
¦ State income tax credit for The decision of the Landmarks Board is subject to call up by the
20% of approved City Council. If a majority of Council votes to call up the
rehabilitation costs (up to Board's decision, it is re-considered at a subsequent City
$50,000 per property) for Council public hearing. If council does not call it up, the
local landmarks and Board's decision is final.
contributing buildings
within historic districts pd~- permit Requirements and Compliance with City Codes
Please note that obtaining a Landmark Alteration Certificate
¦ Federal Investment Tax does not include review of your project for all city
Credit for National requirements. In addition to meeting the guidelines, design and
Register properties used building plans must meet all requirements of the City of
for commercial purposes Boulder Revised Code, including, without limitation, the Land
¦ Eligibility for Colorado Use and Structure Regulations of Titles 9 and 10, B.R.C. 1981.
Historical Fund grants The land use regulations include limitations on building
setbacks from property lines, maximum building heights, and
• The waiver of sales tax on minimum solar access requirements. Building, fire, mechanical
construction materials at and plumbing requirements are covered in the Structure section
the time of building permit of these regulations. The sign code includes limitations on the
application size and placement of signs.
¦ The potential for .For direct
exemptions or variances to questions regarding the building requirements or Land Use
a variety of building code regulations, call the Planning and Development
and zoning requirements. ~tspee#ier~Services Center at 441-X91880.
For complete information Submittal Requirements
on these benefrts contact a The information you submit with your application is the only
Preservation Planner by description the Landmarks Design Review Committee will have
calling (303) 44 I -4~~31880. of your design. It therefore should illustrate, as precisely as
possible, what you have in mind.
For further information or to schedule a review by the
Landmarks Design Review Committee, please contact the
Plannng Department, 1739 Broadway, Suite 300, (303} 441-
429-31880.
GENERAL DESIGN GUIDELINES
Agenda Ilemf_~~# , ~v
The following are required for review:
I. Application.
2. Photographs. Show all the views of the existing
building and at least a portion of the neighboring
buildings.
3. Scaled Site Plan. A site plan shows a view of your
property from above. Show the property boundaries,
existing buildings, significant trees and landscape
features, and your proposed changes. Include a north
arrow and the location of adjacent buildings, streets and
alleys.
4. Elevations. An elevation is a scaled drawing of the front,
rear or side of a building. Illustrate elevations of all
relevant views of the alteration at the same scale to
which the floor plans are drawn. Accurately label them,
and include the existing building with as much detail as
necessary to show how the old and the new relate to
each other.
5. Floor Plans. Include floor plans drawn at a scale of not
less than 1/8" = 1'0". Include a north arrow and show the
existing building and how your alteration relates to it. It
should be complete enough to show any exterior stairs,
porches, decks, etc., and should include a roof plan.
6. Materials. List the visible exterior materials and
describe them as fully as possible. Samples of these
materials are always helpful.
7. Color. If your plans include paint or stain, describe the
color and include a sample of the colors. A good way to
show the color scheme is to color one or more of the
elevations.
8. Models. For new buildings or for proposals that alter
the scale and/or mass of the original building, a scaled
model may be required. Note that models need not be
expensive: a simple massing model can be made by
tracing each elevation onto cardboard, gluing all sides
together, and adding roofs and appurtenances such as
dormers.
- - Aoencm IMm: C a i
INTRODUCTION -
PRESERVATION APPROACHES &
APPROPRIATE TECHNIQUES INAPPROPRIATE
techniques for roofs techniques for roofs
While every historic project is different, the
Identifying, retaining, and Secretary of the Interior has outlined four Altering the roof and
preserving roofs that are basic approaches to responsible roofing materials which are
important in defining the preservation practices. Determining which important in defining the
overall historic character of approach is most appropriate for any overall historic character of
the building. project requires considering a number of the building so that, as a
factors, including the building's historical result, the character is
Protecting and maintaining a significance and its existing physical diminished.
roof by cleaning the gutters
and downspouts and condition. Failing to stabilize a
replacing deteriorated deteriorated or damaged
flashing. Preservation places a high premium on roof until additional work is
the retention of all historic fabric undertaken, thus allowing
Stabilizing deteriorated or through conservation, maintenance and further damage to occur to
damaged roofs as a repair. the historic building.
preliminary measure, when
necessary, prior to Rehabilitation emphasizes the retention Replacing historic roofing
undertaking appropriate and repair of historic materials, but material instead of repairing
preservation work. more latitude is provided for or replacing only the
replacement because it is assumed the deteriorated material.
Repairing a roof by property is more deteriorated prior to
reinforcing the historic work. Failing to reuse intact slate
materials. Repairs may or the when only the
generally include the limited Restoration focuses on the retention of roofing substrate needs
replacement in kind--or materials from the most significant time replacement.
with compatible substitute in a property's history, while permitting
material--of extensively the removal of materials from other Replacing an entire roof
deteriorated or missing periods. feature such as a cupola or
features. dormer when limited
• Reconstruction establishes limited replacement of deteriorated
Replacing in kind a roof opportunities to re-create anon- and missing parts is
feature, such as a dormer or surviving site, landscape, building, appropriate.
cupola that is too structure, or object in all new materials.
deteriorated to repair - if Applying paint or other
the overall form and coatings to roofing material
detailing are still evident - The Secretary of the Interior s website which has been historically
using the physical evidence outlines these approaches and suggests uncoated.
as a model to reproduce the recommended techniques for a variety of
common building materials and elements.
feature. Introducing a new roof
An example of appropriate and feature that is incompatible
Recreating the documented inappropriate techniques for roofs is in size, scale, material and
design of exterior features provided in the sidebars. Additional color.
such as the roof shape and information is available from preservation
coverings. staff and the Secretary's website at:
www.cr.nps.gov/hps/tps/standguide/i ndex. htm
GENERAL DESIGN GUIDELINES
G ~
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SITE DESIGN
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CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD C P~~
33
2. SITE DESIGN
Site design includes a variety of character-defining elements of
our historic districts and buildings. Individual structures are
located within a framework of streets and public spaces that set
the context for the neighborhood. How structures occupy their
site, in terms of alignment, orientation, and spacing, creates
much of the context of the neighborhood. In combination with
public and private walks, fences, tree lawns, landscaping, and
retaining walls, the site design feahires help to define individual
sites and the relationship between public and private space in a
neighborhood.
2. I Building Alignment, Orientation, and Spacing
• ~ ~ ~ ~ • - ~ ~ - ~ ~ ~ The pattern of setbacks is an important element in defining
neighborhood character. A front yard setback serves as a transitional
~ space between the public sidewalk and the private building entry.
I . • When repeated along the street, these yards enhance the character of
~ I the area. The relatively uniform alignment of building fronts, as well
~ as similar spacing between primanJ buildings, contributes to a sense of
visual continuity.
._.._.._.._.._...._..l
~~~.~n
f ; I Traditionally, the primary entrance of a building faced the street and,
~ - ~ . ~ depending on the architectural style of the house, was often sheltered
' I b> a one-sto orc1T. This eature rovided an additional transition
~ - - - ~ - - - ~ ~ ~ - ~ ~ 1 from the public to the private space and helped establish a sense of
scale to the neighborhood.
I
. _ _ _ _ _ _ _ _ ~ _ I The primary structure generally "stepped down" to one stonJ at the
1. ~ ~ 2. rear of the lot. This, and smaller accessory structures along the alley,
The marked building is built outside the helped frame the rear yard-
range of typical setbacks and occupies a
much larger percentage of the back GUIDELINES
yard area than typical.
. I Locate structures within the range of alignments seen
traditionally in the area, maintaining traditional setbacks
at the front, side and rear of the property.
.2 Building proportions should respect traditional patterns in
the district. For example, many areas are characterized by
relatively narrow lots and vertically proportioned front
2.1.2 facades, taller than they are wide. In such an area, it
In areas characterized by vertically would be inappropriate to introduce horizontally
proportioned facades, buildings with a
proportioned front facades.
horizontal emphasis are inappropriate.
GENERAL DESIGN GUIDELINES
~ G ~
.3 Orient the primary building entrance to the street. _ ~ y
~ ti
.4 Preserve the original location of the main entry and walk. {
off!
y
.5 Anew porch may encroach into the existing alignment
only if it is designed according to the guidelines and if it is _ ,
appropriate to the architectural style of the house. ~ ~ ~ "
.6 In neighborhoods with alleys, garages should be located at ~ t~s~, .
the rear of the lot and accessed from the alley. ~ ~ ~ ~ ~
~ ~ 1~
.7 Preserve a backyard area between the house and the
garage, maintaining the general proportion of built mass to
open space found within the area.
2.1.3
2.2 Streetscape and Landscape Traditionally, the primary building
entrance faced the street. The lack of
The overall character of the historic districts is defined by more than a front entrance on this home disrupts
the character of the street.
the buildings. Landscape features of the streetscape, such as the
pattern of street trees and planting strips between the sidewalk and the
curb, form a significant part of the historic character of an area.
Similarly, traditional landscape designs help to imifi~ the district
visually. Lawns and low plantings do
fine open spaces between the
street and the houses. Traditionally, few front yard fences or
landscaping materials obscured the view of the building from the
street. Those traditional patterns should be maintained as the
districts continue to evolve.
GUIDELINES
. I Maintain the established spacing pattern of street trees.
t~~.
.2 Preserve street trees whenever possible. ~
o'~rim
~ "
.3 When a tree must be removed, or where there is a gap in ~ ~ N J~r~
the rh thm of street trees, install new street trees in--~~ ~ ' `
locations that continue to express the established rhythm. k_' , ~ ~ JF~ ~
.4 Maintain the tree-planting strip as a lawn area. The - - t:~~~
~_yt ~ ,
planting strip (the area between the curb or street and the _ ~ ~
- ~ ~~A~_.y
sidewalk) is traditionally simple, consisting of grass or low .
ground cover along with regularly spaced street trees. ~
` x ~ ~
F .t t.1$ ~
Appropriate: xz
¦ Grass or low ground cover and trees. 1.1.4
Inappropriate: Grass, low ground cover, and evenly
¦ Extensive areas of hard sttrface spaced street trees are appropriate for
¦ Elevated planting borders and bushes the area between the street and the
sidewalk.
- llpenda Ilem# C- Prape~,,,,~~
SITE DESIGN
¦ Edging materials such as timber, railroad ties or
masonry, except where there is historic precedent.
.5 Provide a front yard that is landscaped in a traditional
manner with traditional materials.
- - ~ ~ Avoid replacing sod with concrete or any hard surface.
i Edge areas with natural materials such as stone.
~ ` Locate planting beds in traditional areas such as
y ~ - around foundations and along walkways.
~ " The use of railroad ties in landsca in is a recent
_ P g
~ design approach that is not permitted.
~ .
.6 Avoid landscaping that has the potential for damaging a
- ~ historic structure, such as climbing ivy or trees planted too
close to a building.
~ ~~w _
~ _ .7 Where existing retaining walls are important to the
character of the site they should be preserved and
incorporated into new landscape features.
. _
- - Tall, plain concrete retaining walls are inappropriate.
2.2.7 ¦ Regrading and the introduction of new retaining walls
Retaining walls are typically stone or
brick. Plain concrete is inappropriate. 1S lriapprOprlate.
2.3 Alleys
~ ~ ~ The alleys in historic districts were traditionally used for secondary
r„~,,.~~*,.~ ~ x r~ access to the houses, for deliveries, and as storage places for horses and
` buggies, and later, for cars. A view of the backyards from the alleys
~j~, ~~y ~ was maintained. While: today's alleys have evolved into use as
.u:~ edestrian aths or "o 'n , bici clip and do walkin ,the still
p p f l %%t % J % % % y
" ~ ~ contribute to the historic character of the neighborhood. They are
-f~
x. ~ . typically minimally paved.
eti~ a
^n Along the alleys are historic accessory buildings of various shapes and
:A- ~ _ sizes including barns, chicken coops, sheds and small garages. This
varied contributes to the eneral eelin o human scale in the alle s
_ - J % f %f y
LR ,
~ GUIDELINES
.1 Maintain alley access for parking and retain the character
2,3,2 of alleys as clearly secondary access to properties.
Typical alleys are unpaved and
characterized by a variety of small-scale ,2 Retain and preserve the variety and character found in the
accessory structures and access to
parking. existing historic accessory buildings along the alleys.
.3 The use of historically proportioned materials for building
new accessory buildings contributes to the human scale of
GENERAL DESIGN GUIDELINES
~p°"da M°~'~-~-pis
the alleys. For example, narrower lap siding and smaller
brick are appropriate.
.4 Structures that were constructed after the period of
significance but are still more than 50 years old and
contribute to the variety and character of the alleyway
should be retained.
.5 Maintain adequate spacing between accessory buildings so
that the view of the main house is not obscured, and the
alley does not evolve into a tttnnel-like passage.
.6 Generally, paving alleys in historic districts alters the
historic character and is inappropriate.
¦ If paving is necessary, a paving material that preserves
the utilitarian character of the alley is appropriate.
¦ The preferred surface is a permeable, soft-edged
material such as recycled asphalt, that will control
drainage and dust.
¦ In problem areas with persistent potholes and/or
drainage problems, solutions such as regrading and
adding pea gravel should be used.
.7 Lighting in alleys should be low wattage and focused
downward. See also, Sectio~i 8.4 Lighting.
2.4 Parking and Driveways
Historically, private parking was limited to the rear of the lot with At-~EY
access from the alley. There are instances where curb ciets have been r~~ ~ '~r"-"-~'-'~-~~t
added in the front yards, but these are generally later alterations and I i i
do not represent traditional parking patterns. I i i
i i I
GUIDELINES i i i
i i X i
.1 Maintain the traditional pattern of parking at the rear of I I I
the lot. i ~ A I l
'Vi'a
.2 Access to parking should be from the alleys whenever i ~ i i
t
possible. i , ~ i i
i i i
.3 Parking in the front yard is inappropriate. ~ j i
STREET
.4 New curb cuts from the street are inappropriate. When 2.4.1 ~ 2.4.2
adding a garage or significantly altering an existing garage Parking should be provided at the rear
on the alley any front curb cut should be vacated and of the lot and accessed by an alley
C10Sed. whenever possible.
SITE DESIGN ~
~ .5 The visual impact of parking for multi-family and
~ commercial uses should be minimized. Common
a_ ~ approaches include separating parking into small clusters,
~ screening with buildings or landscaping, and the use of
w i small accessory structures.
..r
= ~ .6 Historically appropriate paving materials, such as
a
-tl,~ _ ~i
i ' ~ ~ flagstone or brick, can be used to visually break up larger
parking areas.
~1
J Paving driveways or garage access areas with asphalt or
concrete gives a modem look and is generally
inappropriate, particularly when adjacent to unpaved
2 4 ~ alleys. Flagstone or brick wheel strips are the preferred
This new garage is accessed by alternative.
flagstone wheel strips
2.5 Sidewalks
Many of Boulder's older neighborhoods were originally paved with
flagstone or aggregate concrete. These original walkway materials are
important elements and contribute to the historic character of the
neighborhood. The traditional pattern of walkways perpendicular from
the public sidewalk to the front porches or main entries of the houses
provides unity to the streetscape. New sidewalks must meet the
Americans with Disabilities Act requirements.
GUIDELINES
f n.
<s ! _ . I Retain and preserve original sidewalk materials where
they exist. If replacement of a deteriorated section is
` T necessary, match the original section or element in
y ,r location, pattern, spacing, dimensions, materials and color.
~ ~ :~rj~~„ ~ . ~ Replace flagstone with flagstone.
~ ~ ~ i~., ~ • Replace concrete with concrete. However, if th<< ?
c- face is predominantly paved with flagstone, replacing
~s?l`, - _ ~ concrete portions with flagstone is appropriate.
~ _ µ s., ~I
' .2 New walkways should be designed to be compatible in
_
location, pattern, spacing, dimensions, materials and color
k" .
7 ~ I with existing walkways that contribute to the overall
~ r _ ~ " historic character of the area.
r..' " ~ ~ ~ ' Walk design should be simple and traditional,
2.5. t reflecting the neighborhood and period of
Typical sidewalks are concrete or
Flagstone and simple in design. COristrUCtlon.
¦ Flagstone or traditional aggregate concrete is
encouraged.
Apsl~ Iberni C Pips
GENERAL DESIGN GUIDELINES
.3 Provide a walkway from the street to the primary front
entrance of the building. The walkway should generally
be perpendicular to the sidewalk.
2.6 Fences
The appearance of the house from the sidewalk, street, and alley ~ l
contributes to an area's character. Historically, fences were not , ;
common in Boulder. Where they existed they were very open, low, ~
and used to delineate space rather than to create walled-off privacy ~ - ~ ~
areas. Rear and side yard fences were built low enough so neighbors s~ : "
could talk to each other over them. The fences could be easily seen ~ `
through and were built of woven wire (not chain-link), wrought iron, ,
or painted or opaque stained wood pickets. Elaborate wrought iron i ~s _
and cast iron fences were typically found only on lots with large or - ~ 3_ _
grand homes.u~yw~~r~,~~`' ?
Q ttiL+C ' N
Jzs„~`k - r
Ys
GUIDELINES ~~~;~~~k~.
i t 5 r
.1 Retain and preserve historic fences that contribute to the
historic character of the site or district whenever possible.
Repair deteriorated fence components rather than replace 2.6.2
Many of the historic districts are
them' characterized by open front yards.
Adding new front yard fences in such
.2 Where fences were not traditionally found in the front areas is eenerally inappropriate.
yard and where the streetscape character is defined by
open front yards, the introduction of new fences in the
front yard is inappropriate.
.3 Introduce compatible new fences of traditional materials
only in locations and configurations that are characteristic
of the historic district. New fencing should reflect the
character of historic fences in height, openness, materials, ;
r
~
and finish. ` ~ '
s
.4 Generally, historic fences were constructed of wrought ~ z'a.
iron, wood pickets, or woven wire with an open
appearance and a scale that related to the main building. "
:,a;,
Cedar stockade fences or block walls are inappropriate. ~ ~ ~
a ;may
.5 Generally, historic wood fences were painted or opaque ~ A,w<~,- -
stained. Transparent stains and unfinished wood are
generally inappropriate. The side of the fence facing the 5 ;t
street, alley, and/or sidewalk must be finished. Y
2.6.4
Wrought iron and cast iron fences
.6 Front and rear fences should have some degree of were typically found only on lots with
openness and spacing of slats so that the main structure on large or grand homes.
SITE DESIGN ~
s,~- ' the site is visible from the street or alley. Solid wood
` ~ ~ a, ~ fencing along the rear of a lot obscures much of the
:rte P ~ ~ irregularity and variation that defines the essential
character of an alley and creates an inappropriate "tunnel"
~ effect. Rear and side yard fences below 5 feet in height
y' r~ ~ with a minimum of 1" spacing between the pickets can be
-
reviewed at staff level.
.7 Where appropriate, fences in the front yard should be no
more than 36 inches high. This low height should be
- maintained along the side yard as far as necessary to
~ maintain an unobstructed view of the building's main
architectural features, at least to the front elevation of the
house and/or porch. At that point, the fence may become
gradually higher and less open.
2.6.6
This front yard fence is inappropriate
for both its height and lack of .8 Side yard fences were typically located behind the main
openness. house, not in the front yard. Where side yard fences do
extend into the front yard, they should be low and open
with a gradual transition in height toward the rear yard.
The portion of the side fence that extends beyond the front
` ~k ~y ~ 30 ~
` ~ ~ ' ~ ~ , elevation of the building should not exceed a maximum of
36 inches in height.
_ ~
I
!~~~f !I~~lilll~f~[I1~ ~
x.~~,
x .
~ ;N
2.6.7
This is an appropriately open and low
front yard fence.
t ~)~la
a~ ~ r.
.
F
k
,fiij
i,~
- - r
2.6.8
This side yard fence gradually ~I#~~
transitions from the rear to the front.
GENERAL DESIGN GUIDELINES
ALTERATIONS
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CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD Q ~
3. ALTERATIONS
The difference between "alteration" and "addition" (section 4)
is in the magnitude of change to the original structure.
Typically, an alteration is on a smaller scale than an addition. It
usually involves elements such as adding dormers, decks, and
windows. An addition usually means adding more square
footage and/or external walls.
As with an addition, an alteration should preserve and
complement the historic character of the structure. It should not
replicate but should be distinguishable from and simpler in
design than any historic element. For example, an added
window would not have the elegantly carved frames of a
historic window. In general, simpler designs are the most
successful.
3.1 Roofs, Skylights, and Solar Panels
The roof is one of the primary character-defining features of a historic
TYPICAL ROOF FORMS building, and the repetition of similar roof types creates part of the
visual consistency that defines a historic area. Alterations or
additions to roofs must be given careful consideration to ensure that
i they do not compromise the integrity of the historic structure. Typical
` roof shapes are gabled or hipped. Shed roofs sometimes occur on
historic additions and accessory structures. Buildings within a
district may have a combination of these roof types.
HIPPED GUIDELINES
. I Retain and preserve the original roof form of a historic
structure.
¦ Maintain the roof form, slope, height, and orientation
to the street.
¦ Preserve the original depth of the overhang along the
eaves.
GABLE ¦ Any alterations to a roof should be compatible with the
form, pitch, plate height and massing of the historic
r-'-- -
~a__` roo .
~ Raising the roof to accommodate a full or partial upper
~ t story addition is inappropriate -consider the addition
\ i of a dormer instead.
f
-
SHED •2 Preserve the character of the original roofing and its
details.
¦ Although historical accuracy in roofing materials is not
Winter & Company required, attempt to preserve the type, unit scale, and
- GENERAL DESIGN GUIDELINES
texhtre of the original roofing. In some circumstances, ~
the roofing material is an important architectural -
feature that should be preserved. For example, metal
roofs should remain metal; tiled roofs should remain
tiled. _ -~k ~ y
¦ Boulder has an ordinance that requires the phasing out ~
- ~ -
wood shingle roofs. Dimensional, composition ~ t~
shingles are an appropriate replacement. ~ h` Cry ~ ~ r~ ~
V ~C~ ~
¦ Avoid removing historically important roofing or s ~n
wood trim that is in salvageable condition. Retain and
repair roof detailing such as brackets, cornices,
parapets, bargeboards and gable-end shingles. _
.3 Skylights that are installed on a historic roof should be as
unobtrusive as possible and not visible from a public 3.1.3
street. Flat skylights that blend with the roof are most Bubble-type skylights are inappropriate,
appropriate. Sculptural or bubble-type skylights are not especially when visible from the street.
appropriate. Also see Guideline 8.3.4.
.4 Minimize the visual impact of solar collectors. Also see ' ~ ~ ~ ~
Guideline 8.3.4. ~ i~ .
¦ The use of energy-efficient and energy-conserving
materials is encouraged, but they should not ,
y
compromise the historic integrity of the building. -
¦ Solar collectors should not alter the existing profile of ~ ~ ~ ~,f
the roof nor be highly visible, particularly from the
front of the house. They should be mounted flush on
rear-facing roofs, or placed on the ground in an
inconspicuous location.
.5 Roof appurtenances such as swamp coolers, TV antennas, ~ - _ u
and satellite dishes should be installed so that they are not i.~ '
visible from the street and do not damage or obscure 3.l .s
historic features. Also see Guideline 8.3.4. Mechanical equipment, such as coolers,
should not be visible from the street.
3.2 Roof Decks and Balconies
Roof decks are deck areas above the first floor drat are contained
completely or partially in a roof mass. Balconies are railed or
balustraded platforms that project from the building. Second story roof
decks or balconies are characteristic of only a few architectural stiles
found in Boulder. They may be compatible additions, however, if
located on the rear and if they are integrated into the primary
structure. Second story roof decks or balconies are not appropriate for
free-standing accessory buildings and garages. Any decks or balconies
ahove the second story are inappropriate unless based on historic
precedent.
C
ALTERATIONS
GUIDELINES
. I Locate roof decks or balconies on the rear, not on the front,
of the building. Front roof decks or balconies are
appropriate only if recreating a documented historic
,F J
element.
~ 'i .2 Integrate the roof deck or balcony into the structure either
EiBBr Rn 88 ne a®~,'rnact
~ _ _ by setting it into the building or by incorporating it into
the roof structure.
.3 Avoid cantilevered projections from the building, and use
• appropriately scaled brackets or supports.
3 2 2 .4 While current code requirements must be met, new
This rear roof deck is appropriately railings should be as close as possible to historic heights.
integrated into the roof. In addition, sensitive design may give the appearance of
the lower railing heights found on historic structures.
3.3 Decks
Decks are modern expressions of porches that were not found on
historic buildings. Great care needs to be taken in designing decks to
fit into the historic character of the house. The design elements must
respect the historic character as to size, materials, railing detail,
intrusion into spaces between buildings, and materials. Because decks
are not traditionally found on historic structures, they should be
avoided or their appearance should be minimized. Decks should be
subordinate to the house in terms of seaIe and detailing.
GUIDELINES
For second story decks, see 3.2 Roof Decks and Balconies.
. I First floor decks are inappropriate in the front of a house.
Locate a first floor deck to the rear of a building.
.2 While current code requirements must be met, new
railings should be as close as possible to historic heights.
In addition, sensitive design may give the appearance of
the lower railing heights found on historic structures.
.3 Unpainted redwood is inappropriate; decks should be
painted or stained to match the existing building.
.4 Materials with a synthetic look and/or feel should be
avoided.
GENERAL DESIGN GUIDELINES
C 4a
3.4 Porches
Front orches are a common and im ortartt visual element o mart ~ '
n p p f y
historic building styles. The porch roof is generally supported by F n
freestanding columns or by columns resting on a masonry wall. Wood y, ' ~
railings are anchored with masonry or wood balustrades. A porch is ~ `
generally open with the facade of the house plainly visible. ~T `
GUIDELINES 4
I v t T a
. I Original porches should be preserved. ~ ~
~..i~
.2 Deteriorated original porches and porch elements, such as ;t,. ~ ~~1
railings, balusters and columns, should be repaired or
replaced, following recognized preservation methods so ~ ~ I
that the character of the porch is not compromised. - ` . ;
.3 Maintain the height, detail and spacing of the original ~ ~ i~ ~ , .
balustrade if replacing, extending or adding balustrades. '~ti', ~ •
4. ` a
.4 Enclosing a front porch negatively impacts the visual ~ ~ ~r„'
character of both the individual house and the streetscape 'T:~~,, } - Y~~,
and is inappropriate. I ~ ~
.5 If a rear or side porch is to be enclosed, the following
guidelines apply: ~ ~
¦ Maintain the sense of openness, scale, proportion, and
separation from the structure of the house. The
enclosure should not obscure the main architectural
~ :y
details of the porch or house. 1, ~ Y+. 7
¦ Keep the design and materials as simple as possible _
rather than trying to match the building facade. Front porches are key character-
defining features of both individual
.6 Rebuilding a missing original front porch is encouraged if buildings and the streetscape.
evidence of the original porch can be documented.
.7 The introduction of new porches that were not present
historically is inappropriate on individual landmarks and
buildings that are contributing to a historic district.
.8 Porches on new buildings or on non-contributing
buildings should be compatible with the architecture of the
building, incorporating traditional scale and proportions
with updated design details.
.9 Large, two-story tall porches are inappropriate for front
facades unless present historically.
llperide Memf C Psps# ~'S
ALTERATIONS
. i
3.5 Dormers
Dormers are traditional roof elements that either extend the space
~ % ~ under the main roof or serve as decorative elements to the main roof.
They generall y follow the pitch and form of the main roof and are
~ ~ always secondary to the main roof massing. The introduction of
dormers may dramaticall y change the building's appearance, and
f therefore may not be appropriate in all circumstances.
GUIDELINES
. I Existing dormers are important character-defining features
4 of a building and should be preserved, particularly those
~ ~ ~ that are most visible from the street.
~ /i
.2 Deteriorated elements should be repaired or replaced,
following recognized preservation methods.
Winter & Company
3.5.4 .3 Existing dormers should not be enlarged or altered in any
Dormer forms should match roof way that changes their secondary relationship to the main
forms; e.g. gabled roofs should have
gabled dormers and hipped roofs roof.
should have hipped dormers.
_ .4 The size, scale, and style of new dormers should be
compatible with existing dormers on the structure. The
~ form of roof dormers should be compatible with the main
roof form.
~ . .5 Dormer windows should be similar in proportion to first
.
and second floor windows but smaller.
n ~
.6 New dormers must be subordinate to the main roof in
i
~ terms of mass, scale and height. Notwithstanding the fact
~ ;~'~'`~h that one large dormer may give the greatest usable space
within the roof form, smaller dormers are usually the most
E---- y appropriate. Often two small dormers are more
3.5.6 / 3.5.7 appropriate than one large dormer.
The size of these dormers overwhelms
the main roof and the ridgelines are
even with, rather than below, the main •7 Dormer ridgelines must be lower than the main roof.
roof.
G
GENERAL DESIGN GUIDELINES
3.b Exterior Materials: Walls, Siding, and Masonry
Brick, stone, horizontal wood-lapped siding, stucco, and wood shingles ~,~,,,~,,,~.••-A*--~-: - >
are common finish materials found in historic districts and on historic ~
structures. Over the years, the materials used in residential ~
construction have not changed dramatically, but the scale of materials ~ i ~s ~ ~
has become larger. Narrower lap siding, smaller brick and shingles , r~ .,.~=~~r°~ ,r..,'
used alone or in various combinations often distinguish older homes ~
..rY~~
from newer ones. Brick and stone masonry were traditionally left
natural while wood surfaces were painted. - -
~ ~.~E k
GUIDELINES „
~f .
. I Original historic finish materials should be preserved and _
repaired. ~~t, t-~;.,,>f' ~ _'~~~r'K~
¦ Unpainted masonry surfaces, particularly those with ~ ~"'r"`~ `xR~`
historical significance, should not be painted. ,t ~ ; ~
k
¦ When feasible remove newer materials that have been ~ a
applied over historic finishes and that have not c~"~ ~.~.~xe
achieved historic si ificance in their own ri ht. _
Removal of non-historic materials such as shtcco or I ~ r ~ ~~4.,,
permastone must be tested to assure that the original ~ ~ s
material will not be damaged in the process. ~'T ~
¦ When repairing masonry use appropriate mortar, i.e., ~ ' '
one that is softer than the surrounding masonry. ' i
~
L~
.2 New finish materials should be compatible with, but not t
seek to replicate, original finish materials. I ~ `
¦ Use materials that are similar in scale, proportion, . , ~ ~
texture and finish to those used historically. ~
¦ Use authentic materials -materials made to look like Historic materials such as wood siding,
other materials, such as concrete that is scored to look stone, brick and dimensional shingles
like brick, are riot appropriate. help establish human scale.
3.7 Windows, Storm Windows, and Shutters
Windows, the elements that surround them, and their relationship to
ore another are one of the most important character-defining elements
of a historic ~~buildinQ and should be preserved. Improper or
insensitive treatment of the windows on a historic structure can
seriously detract from its architectural character. The relative
importance of a window depends on three factors: the location o the
window on the building, the historic significance of the window, and
its condition. Windows on files-elevations visible from public
:~w~ partieularl y the frer~-facade, are especially important. A
window that has a high level of historic si~ificance, regardless ofd is
location, ma~also be verb irn op rtant_to the historic inte~rittt of the
- Agenda Memo G p®pei_~~
ALTERATIONS
i
buildin~.-
p~The replacement o f historic windows should be considered
only as a last resort.
At times, propert~a owners consider replacement of their historic
windows as a wau of imtirovin~g~efficiencu. While the energy
loss of a building maid be reduced b2~ replacing or repairing historic
windows, windows are onlu one factor in the building's energu usage.
It is recommended that a comprehensive energy audit be undertaken to
identifu areas for imtirovement. To increase a buiIding's energy
e ~ciencu, a combination o air sealin ,additional wall and ceiling
insulation, and the adiustment of mechanical sustems is generally
more effective than ocusin~ onI» on the repair or replacement of a
window. For more information regarding ener~e 'ciencU and enerQu
audits for historic buildings, tilease contact the O 'ce o~
Environmental Affairs at www.environmentala{fairs.eom
cA',~' `Y
` GUIDELINES
~3
- ~ ,r : Protection of Historic Windows
~T . I Retain and preserve existing historic windows, including
A their functional and decorative features, such as frames,
'~r~ sashes, muntins, sills, heads, moldin s, surrounds and
_ g
~ ~ ~ hardware. Because windows near the f~ex~-facade are
_ ~ particularly critical to the character of historic buildings,
their protection may supersede the protection of historic
windows elsewhere. 1n some cases, it maybe appropriate
to use window elements from rear or side elevations to
repair those on the front.
.2 Preserve original window locations; do not move windows
from their historic placement.
.3 Repair rather than replace the functional and decorative
features of original windows through recognized
preservation methods. If replacement of a feature is
necessary, replace only the deteriorated feature in kind
rather than the entire unit, matching the materials, design
and dimensions of the original.
Retrofit of Historic Windows
.4 In some cases, retrofitting historic windows to make them
more energky efficient ma~pgrogriate as dart of a
window rehabilitation pro ram. T~ically a window
GENERAL DESIGN GUIDELINES
retrofit preserves most or all of the historic wood, glass~or
metal components and consists of insulatin , weight
pockets and complete weather stringing of its sash and
frames. If a window retrofit calls for the replacement of
single pane glass, it is important to determine that the
work will not compromise the historic character of the
building or the district in which it is located. Historic lg ass
is typified by its "wavy" uneven surface which can be an
important character defining feature of a window and the
historic building as a whole. Depending upon its location
on the building, the importance to the window itself, and
relative condition, the replacement of historic glass maybe
inappropriate.
• Retrofitting_historic true divided light windows with
thermal-pane glass is inappropriate on primar~or
secondary elevations.
• Retrofitting historic windows on primary elevations is
rarel~p~ropriate unless the glass has been replaced
with non-historic lg ass.
• The dimensions and relationship of replacement glass
to the stiles, rails, and muntins must closely match
those of the unimproved window.
• The retrofit of historic sash with visibly tinted or
reflective glass is inatinropriate.
• The introduction of weather stripping insulation, or
materials to improve the operation of historic
windows must not be visible from the exterior of the
building.
Window Replacement
.5 The repair of historic windows and doors is alwav~s
preferr~ as part of a rehabilitation proiect. Research
indicates that, in most cases, the energy efficiency of an old
window can be increased to that of a thermal pane
replacement by weather-stripping, insulation of weig=ht
pockets, and the application of an interior or exterior storm
system. However, if the property owner wishes to recluest
a landmark alteration certificate to replace windows on a
contributing or individually landmarked building} the
steps as outlined in the Historic Window and Door
Replacement/Retrofit Guidelines must be followed.
i
l~e_-replaced te-r~tt~tl~r~inal. ~h-~,.~,Led
ALTERATIONS ~
.6 The location of the window(sl proposed for retrofit or
replacement is important in assessin ,their si ~ icanc
a historic building. In general, the more important the
elevation where the window is located, the less likely that
retrofit or replacement will be appropriate. Elevations will
be categorized as primary, secondar~or tertiary, using the
methodolo~v set out in the Window & Door Replacement
Application and Survey.
• Replacement of intact historic windows on primary
elevations is rarely appropriate.
• Replacement of intact historic windows on secondary
elevations is Qenerally inappropriate.
• Replacement of intact historic windows on tertiary
elevations can occur provided it does not compromise the
historic integrity of the building.
.7 The historic significance of the windows~roposed for
replacement must also be assessed. In general, the more
significant a window is to the building as a whole the less
likely that a retrofit or replacement will be appropriate.
The appropriateness of a window replacement will be
determined, in part, based upon characterization of the
window as either'Very Historically Important'F
'Historically Important', or'Non-Historic' (See
Definitionsl.
l~~~i;
.8 The condition of the window must be evaluated prior to
determining whether the window or door maybe repaired
or replaced. The condition is to be determined b~ assessing
its elements individually. The assessment must be
completed through the use of a survey that identifies the
extent of deterioration in each window and determines
whether the windows may be repaired, retrofitted, or
replaced. The survey form documents the existing
condition for the window and identifies which features
will be repaired and which will possibly be replaced.
GENERAL DESIGN GUIDELINES
Aoenda Me~ri# ~ P~ae ~
i i
i / ~ ~ _
.9 If, through the Window & Door Application & Survey, it is _
determined that the window sashes are too deteriorated to
repair (Class III & IV), but the window frames are
salvageable, then sashes only should be replaced to match
the original per the Retrofit or Replacement Section.
f _
_
• 3.7._8
1Z .
True-divided light windows have
individual panes of glass separated by
muntins. While some high-quality
simulated-divided light windows may
be acceptable as replacements in some
cases, true-divided light windows are
most appropriate.
.10 If, through the Window & Door Application & Survey, it is
determined the window may be replaced (Class III & IVI,
the window opening itself should be carefullypreserved.
It should not be made lamer or smaller to accommodate a
differently sized window.
.I I If, through the Window & lloor Ap~nlication & Survey~it iris
determined the window maybe replaced (Class III & IV),
the same material as was the original is most appropriate; _
however, other materials may be considered if the
operation, dimension, profile, and finish are the same.
. 12 If a window that is divided into several panes of glass
must be re~laced~ a similar true-divided-light window that
matches the dimensions, profile and detailing of the
original is most appropriate. High quality simulated-
divided-light windows may be allowed if thev maintain
the muntin size of the original window. Snap-in muntins
or other inauthentic architectural details are inappropriate
. 13 I Iistoric steel windows are character-defining features on
some buildings in historic districts. Because windows
manufactured from other materials generally cannot match
the thin profiles of steel, replacement may not }~e
~pro~riate.
llpwldo ~em;~
C
t~~ 51
ALTERATIONS
.14 If the existin condition of the window(s), as documented
>?Y a Window & Door Survev, indicates Class III or IV
damage or deterioration, then the window(s) may be
retrofitted or replaced. All retrofitted or replacement
windows must match the historic feature as closer as
f;,\ ossible.
Windows in New Construction
rl-A. 15 Windows in additions and new structures should reflect
the window patterns and proportions of the existing
structure and the district and utilize similar materials. For
~r
elevations visible from public streets, the relationship of
},~~n~
~ solids to voids should also be compatible.
~
~ ~ -1-E.16 Windows should be trimmed with materials similar in
scale, proportion, finish, and character to those used
y.
~ ~ ~ traditional)
3.7.J
5~9 / 3.7.+4J 9 17 Openings should indicate floor levels, and should not
The relationship between the amount occur between floors.
of window and wall in this home is out
of proportion with traditional designs.
The odd shaped windows at the roof ~3• 18 Symmetry or asymmetry of openings should be maintained.
peak are also incompatible with hhtoric
patterns. r}~.19 Odd window shapes such as octagons, triangles, and
diamonds are generally inappropriate.
Shutters and Storm Windows
-5.20 Use shutters only if appropriate to the style of the house.
The introduction of exterior shutters to a historic buildings
when there is no evidence that shutters were a historic
feature of the house, is inappropriate.
x-6.2 I Reintroducing missing shutters is encouraged if
evidence of the original shutters can be documented.
x.22 While shutters need not be operable, they should be
sized to maintain the appearance of operability.
-15.23 Improving the energy efficiency of older windows can
often be addressed through simple repairs. Storm
windows or interior energy panels are alternatives to
window replacement. Wood storm windows are
preferred. Metal storm windows maybe appropriate if the
frames match the proportions and profile of the original
windows and if the frames are anodized or painted sv that
raw metal is not visible. Interior installation is preferred.
GENERAL DESIGN GUIDELINES
~laa Nem ~ C ~ ~ 52•
r'te` . { '`5~~,~,
3.8 Doors and Storm Doors ~ _ s
~ .m
;v,
Front doors and primary entrances are among the most important -
elements of historic buildings. The original size and proportion of a ~-ti ; r i
front door, the details of the door, the door surround, and the = ~
placement of the door all contribute to the character of the entrance. r~.~..,
an x~
Propertu Owners mau wish to re~laee their historic doors to improve ,t
energ~e~iciencu. Research indicates that, in most cases, however, the ~ ...a1.d~x , 'a
ener~efficiencu of an old door can be increased to that o anew ~ "~r
~laeement door bu weather-strigpin~ and the application of an ~..,:j
interior or exterior storm door sustem. However, if a propert ou carter r.'
wishes to request a landmark alteration certificate to replace doors on a
contributing or individuallu landmarked building, the steps as - . - -
outlined in the historic Window and Door Replacement/ Retrofit - -
.
Application Guidelines must be followed. '
GUIDELINES An appropriate door in terms of size,
proportion and detailing.
.I nnc~-Whenever possible, retain and preserve all
original doors and door openings. The location of the
door(s~roposed for retrofit or replacement is ~ I ' ~ ~
important in assessin tg heir significance to a historic ~7 °
s.
building. In general, the more important the ~3 'y
elevation, the less likel.
tv
hat
replacement of a historic ~ ~ ~~~i
~
door will be a pro riate. Elevations will be ` = ~ `
categorized as primary, secondarv, or tertiary, using : '
the methodology set out in the Window & Door ~ ' ~ ~ Y~~.
Re lacement A nlication and Survey. ~ ~ ~
• Replacement of intact historic doors on ~rimarv ~
elevations is rarel~gpropriate. ~
• Replacement of intact historic doors on secondarv ' ~ - _
elevations is generally inappropriate. - y a
z~ a° :
~__ReElacement of intact historic doors on tertiary ~ - ~ ~
elevation can occur provided it does not compromise
the historic integrity of the building,.
.2 The historic si ificance of the doors ro osed for 3s.LOs
- - ~ -~-~-ham The modern detailing on this door
replacement must also be assessed. In~eneral, the more would be inappropriate for most
significant a door is to the house as a whole. the less likely homes in Boulder's historic districts.
that a retrofit or replacement will be appropriate. The
appropriateness of a door replacement will be determined1
IRper>Ida Nam f C p8ge #
ALTERATIONS
in part, based upon characterization of the door as either
'Very Historicall~portant', 'Historically Important', or
`Non-Historic'. (See Definitionsl.
.3 The condition of the door(s) shall be evaluated prior to
determining whether the door(sl should be repaired or
replaced. The condition is to be determined b~ assessing
its elements individually The assessment will be
completed through the use of a survey that is intended to
identify the extent of deterioration in each window and to
determine whether the windows should be repaired,
retrofitted, or replaced. The survey form documents the
existing condition for the window and identifies which
features will be repaired and which will possibly be
replaced.
~.4 Retain and preserve the functional, proportional and
decorative features of a primary entrance. These features
include the door and its frame, sill, head, jamb, moldings,
and any flanking windows.
~.5 Historic hardware, hinges, locksets, and knobs are door
features that are significant and should be preserved.
~.6 Repair damaged original doors and door assemblies
whenever possible following recognized preservation
methods.
,3.7 If, through a Window
& Door Application Surveyplacement is found to be
~propriate, the replacement door should match the
original as closely as possible. If documentation of the
original door is not available, then the appearance of the
replacement door should be based on original doors on
similar historic structures.
:6.8 Replace wood doors with wood doors. Although good
synthetic materials are available, the use of historic
materials is recommended.
~.9 If energy conservation and heat loss are a concern,
consider using a storm door instead of replacing a historic
entry door. Generally, wood storm doors are most
appropriate. A metal storm door may be appropriate if it is
simple in design and if the frame is anodized or painted so
that raw metal is obscured.
Agendg NlMni
C ~t~p~~'
GENERAL DESIGN GUIDELINES
:$10. Doors in additions and new structures should reflect the
proportions (height and width) of doors in the existing
structure and/or the district.
.Doors should be trimmed with materials similar in scale,
proportion, finish, and character to those used
traditionally.
ALTERATIONS ~Idi ~111~
~_~~@#~~
ADDITIONS TO HISTORIC
STRUCTURES
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CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD
4. ADDITIONS TO HISTORIC
STRUCTURES
This section applies to buildings that are individual landmarks
or are within a historic district and have been identified as
Contributing, Contributing-Restorable, or Significant Newer.
(see p. 7 and Glossary). Additions to non-historic structures are
considered in Section 5. While the guidelines in this section do
not specifically apply to those properties, they do represent
design principles that should be considered in any addition.
It is normal for buildings to evolve over time as additional
space is needed or uses are accommodated. New additions
within the historic districts are appropriate as long as they do
not destroy historic features, materials, and spatial relationships
that are significant to the original building and site. They also
must be distinguishable from the historic architecture.
New additions should not compromise the integrity of the
original structure or site, whether through direct destruction of
historic features and materials or indirectly through their
location, size, height or scale.
Additions should be compatible with, but discernible from, the
historic architecture. When the original design is duplicated the
addition is indistinguishable and the historic evolution of the
building becomes unclear. Conversely, when design elements
contrast too strongly with the original structure the addition
will appear visually incompatible.
The appropriate location of an addition to an existing building
will depend on the character of the existing building and its site,
adjacent buildings, and the area as a whole. While every site is
unique, generally additions are most appropriate at the rear of
the structure. The addition should be designed and located so
that significant site features, including mature trees, are not lost.
An addition should not overpower the site or dramatically alter
its historic character, and should be subordinate to the existing
structure.
The primary focus in reviewing additions will be on aspects of
new construction that are visible from public streets. The
guidelines will be applied most stringently to these publicly
visible areas. More flexibility will be allowed for rear elevations
and other areas largely screened from public view.
GENERAL DESIGN GUIDELINES
4.1 Protection of Historic Structures and Sites ~ - ~1
i i I
i i I
The primary concern of the Landmarks Board in reviewing additions
to historic structures is the protection of the existing structure and the I I
i i I
character of the site and district.
I I I
GUIDELINES ~ ~ i
i i I
. I Construct new additions so that there is the least possible I L ~ I ~G~`. ~ i
loss of historic fabric and so that the character-defining I .i.~x I r~, !
i i I
features of the historic building are not destroyed,
damaged, or obscured. i i I
i i I
.2 New additions should be constructed so that they may be i.._.__.._,._.._i_._.
removed in the future without damaging the historic STREET
structure. 4.2.
Additions can be distinguished from the
.3 It is not appropriate to construct an addition that will original building by being set in,
detract from the overall historic character of the rind al allowing the corners of the historic
p p building to be visible.
building and/or the site, or if it will require the removal of
significant building elements or site features.
4.2 Distinction from Historic Structures
,
All additions should be discernible from the historic structure. When - b~ ~ ' ~~r ,
the original design is duplicated the historic evolution of the building ~ a~; r~°'
becomes unclear. Instead, additions should be compatible with the . , i ~
historic architecture but clearly recognizable as new construction. i ~
GUIDELINES i
. I Distinguish an addition from the historic structure, but
maintain visual continuity between the two. One common
method is to step the addition back and/or set it in slightly
from the historic structure. Every project is different and
successful designs may incorporate a variety of
approaches. ~ ~
s'
.2 Do not directly copy historic elements. Instead, interpret ~ - - ,
historic elements in simpler ways in the addition. ~'t...~_ ~ ~
.3 Additions should be simpler in detail than the original
- ~ ,
structure. An addition that exhibits a more ornate style or
implies an earlier period of architecture than that of the 4.2.2
Orlglnal 1S inappropriate. The upper photo shows a historic
window. The lower photo shows a
simplified interpretation of the design
.4 The architectural style of additions should not imitate the on an addition to the home.
ADDITIONS TO HISTORIC STRUCTURES C P~;~
historic style but must be compatible with it. Contemporary
style additions are possible, but require the utmost
attention to these guidelines to be successful. The use of
two distinct historic styles, such as adding Tudor-style
half-timbering to a Classic Cottage, is inappropriate.
4.3 Compatibility with Historic Structures
Introducing new construction that contrasts sharply with an existing
historic structure or site detracts from the visual continuity that
marks our historic districts. While additions should be distinguishable
from the historic structure, they must not contrast so sharply as to
detract from the original building and/or the site. Additions should
never overwhelm historic structures or the site, in mass, scale or
detailing.
GUIDELINES
. I An addition should be subordinate to the historic building,
limited in size and scale so that it does not diminish or
visually overpower the building.
.2 Design an addition to be compatible with the historic
building in mass, scale, materials and color. For elevations
visible from public streets, the relationship of solids to
voids in the exterior walls should also be compatible.
.3 Adding a partial or full story to the historic portion of a
i .
' historic building is rarely appropriate.
~~t~ ~`0~~~a~~~M~
r
~ , ~ .4 Reflect the original symmetry or asymmetry of the historic
4.3.4 / 4.3.5 building.
This addition, while subordinate to the
historic building, skews the building's .5 Preserve the vertical and horizontal proportion of a
original symmetry and vertical
proportion. building's mass.
4.4 Compatibility with Historic Site and Setting
Additions should be designed and located so that significant site
features, including mature trees, are not lost or obscured. The size of
the addition should not overpower the site or dramatically alter its
historic character.
GUIDELINES
. I Design new additions so that the overall character of the
GENERAL DESIGN GUIDELINES
Aoerld~l Items ~ Peron ~ ~J°~
site, site topography, character-defining site features and z - -
trees are retained. ~ ~
-
.2 Locate new additions on an inconspicuous elevation of the ~ _ j ti R
historic building, generally the rear one. Locating an I
~ 1 ~'~s,
addition to the front of a structure is inappropriate because ~ •i ;
it obscures the historic facade of a building. I, ~ .
w~,
.3 Respect the established orientation of the original building ,r ; Y,,
and typical alignments in the area. ~ ,
? ~?~?..~_f..._c~
.4 Preserve a backyard area between the house and the a. I • I a.a.2
garage, maintaining the general proportion of built mass to A series of inappropriate additions to
this historic building have completely
open space found within the area. See Guideline 2.1.1. obscured the front fa4ade and
destroyed historic fabric.
4.5 Key Building Elements
Roofs, porches, dormers, windows and doors are some of the most ~_y',.
im ortant character-de 'nin elements o ant buiIdin As such, thei ,~5~'°~'~~~~ ~
require extra attention to assure that they compliment the historic ~ _ ~
s} -f:
architecture:. In addition to the guidelines below, refer also to Section '.F r ~ , '
3.0 Alterations for related suggestions. s ~ ~ $ , x
~
GUIDELINES i ~ _
,
fc'..~
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Roofs
.1 Maintain the dominant roofline and orientation of the roof
_
form to the street. . V,
.2 Rooflines on additions should be lower than and
secondary to the roofline of the original building.
4.5.1
.3 The existing roof form, pitch, cave depth, and materials The roof form of an addition should
Should be used for all additions. • generally be the same as the form of
the original roof.
Dormers
.4 If consistent with the architectural style of a historic
structure and appropriately sized and located, dormers
may be an appropriate way to utilize upper story space.
Windows
.5 Maintain the proportion, general style, and symmetry or
asymmetry of the existing window patterns.
.6 Use window shapes that are found on the historic
structure. Do not introduce odd-shaped windows such as
octagonal, triangular, ordiamond-shaped.
- _ Ap~lda Nenl~ C
ADDITIONS TO HISTORIC STRUCTURES
.7 Do not add divided light windows to structures that
historically did not have divided light windows.
.8 Use materials and construction similar to historic
windows. Do not use snap-in mullions.
I
Apetlda Nem# C Pale
GENERAL DESIGN GUIDELINES
ADDITIONS TO NON-HISTORIC
STRUCTURES
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CITY OF BOULDER J~~,
LANDMARKS PRESERVATION ADVISORY BOARD ~ P~~--~-
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5. ADDITIONS TO NON-HISTORIC
STRUCTURES IN HISTORIC DISTRICTS
This section contains guidelines for additions to buildings that
have been determined to be non-contributing to a historic
district. Non-Contributing buildings include those that,
although constructed during the district's period of significance,
have been altered to such an extent that the historic integrity is
lost and restoration is not possible. Buildings constructed
outside the period of significance and that are not individually
significant (Individual Landmarks or Significant Newer) are
also considered Non-Contributing.
In general, the guidelines for additions to non-contributing
buildings are more flexible than those for historic buildings,
with the exception of site design guidelines (Section 2.0 Site
Design) and the respect for the mass and scale of the district.
Projects will be evaluated based on these issues and the overall
impact on the character of the district.
While non-contributing buildings are not requixed to follow the
guidelines in Section 4.0 Additions to Historic Structures, such
projects may benefit from the design principles suggested by
them.
For substantial alterations to anon-historic building, see Section
6.0 New Structures. Substantial alterations are those that would
require issuance of a demolition permit if the building were
over 50 years of age.
GUIDELINES
. I Follow the guidelines in Section 2.0 Site Design
.2 It is not appropriate to construct an addition that will
detract from the overall historic character of the district by
overwhelming existing buildings in mass and scale.
.3 Alterations to non-contributing buildings built in a
recognizable architectural style should preserve and
respect that style.
~ GENERAL DESIGN GUIDELINES
NEW PRIMARY STRUCTURES
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CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD ~
~ ~
6. NEW PRIMARY STRUCTURES
New construction within a historic district can enhance the
existing district character if the proposed design and its siting
reflect an understanding of and a compatibility with the
distinctive character of the district. While new construction
should fit into the historic character of the district or site, it
should not replicate historic styles. Instead, new buildings
should relate to the fundamental characteristics of the historic
district or landmark site while also conveying a contemporary
style. New buildings should not overshadow existing historic
structures. Fundamental characteristics to be considered in
designing compatible new structures include: site and setting,
building size and proportions, materials, and the placement and
style of doors and windows.
The primary focus in reviewing new structures will be on
aspects that are visible from public streets. The guidelines will
be applied most stringently to these publicly visible areas.
More flexibility will be allowed for rear elevations and other
areas largely screened from public view.
6. I Distinction from Historic Structures
~ 1 "rl i ,1+` ' The replication of historic architecture in rtew construction is
R ~ '`s:~ ,G_..~~`'~'~ inappropriate, as it can create a false historic context and blur the
distinction between old and new buildings. While new structures
' ~ - must be compatible with the historic context, they must also be
recognizable as new construction.
s ~ ~w
GUIDELINES
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~ ,~ti a~'"4 . I New construction should be a product of its own time.
I ~ I Create compatible contemporary Interpretations of htstonc
f ~ s ~ t. , ~ I
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.2 Interpretations of historic styles may be appropriate if they
b.l.l
A contemporary interpretation of a are distinguishable as new.
historic element.
6.2 Site and Setting
New structures should be designed and located so that significant site
features, including mature trees, are not lost or obscured. The size of
the new structures should not overpower the site or dramatically alter
its historic character. Buildings within hisforie districts generally
display a consistency in setback, orientation, spacing and distance
GENERAL DESIGN GUIDELINES
between adjacent buildings. Them fore, the compatibility of proposed
new construction will be reviewed to ensure that these elements are
maintained.
GUIDELINES
. I Conform to the design guidelines found in Section 2.0 Site I
Design, regarding site and setting in developing a ~ ~
proposed site plan. ~ j
I
.2 Design new construction so that the overall character of I - ~
the site, site topography, character-defining site features s'
and trees are retained. _ _
`~~_'f. _
.3 Site new construction to be compatible with surrounding j ba
buildings that contribute to the overall character of the ~ ~ Y~ I
historic district in terms of setback, orientation, spacing, '
and distance from adjacent buildings.
j I
.4 New construction should not be significantly different '
from contributing historic buildings in the district in terms ' ' - ' ' - ' ' - ' ' ' - ' '
of the proportion of built mass to open space on the 6.2.2 / 6.3.2
The marked building is built outside the
lndlvldual site. See Guideline 2.1.1. range of typical setbacks, occupies a
much larger percentage of the lot than
.5 New primary structures should serve as a guide for new typical, and is generally out of scale
accessory structures on the site. Conform to the design With surrounding buildings.
guidelines found in Section 7.0 New Garages and Other
Accessory Structures.
6.3 Mass and Scale
Irt considering the overall compatibility of new construction, its
height, forrn, massing, size and scale will all be reviewed. The overall
proportion of the building's front fa;,ade is especially important to
consider since it will have the most impact on the streetscape. While
new construction tends to be larger than historic buildings, reflecting
the needs and desires of the modern homeowner, new structures
should not be so out-of--scale with the surrounding buildings as to
loom over tlu~m.
GUIDELINES
.1 Design new buildings to be compatible with surrounding
buildings that contribute to the overall character of the
historic district in terms of height, size, scale, massing, and
proportions.
NEW PRIMARY STRUCTURES Agerlde Nem# ~ R~pet '"o
.I
.2 The mass and scale of new constntction should respect
neighboring buildings and the streetscape as a whole.
.3 Historic heights and widths as well as their ratios should
be maintained. The proportions of the front facade are
particularly important and should be compatible to those
of surrounding historic buildings.
.4 Anew house constructed behind an existing historic house
should be of lesser mass and scale than the original
structure.
6.4 Materials
GUIDELINES
.1 Materials should be similar u1 scale, proportion, texture,
finish, and color to those found on nearby historic
structures.
.2 Maintain a human scale by avoiding large, featureless
surfaces and by using traditionally sized building
components and materials.
6.5 Key Building Elements
Roofs, porches, dormers, windows and doors are some of the most
important character-defining elements of any building. As such, they
require extra attention to assure that they compliment the historic
architecture. In addition to the guidelines below, refer also to Section
3.0 Alterations for related suggestions.
GUIDELINES
. I Design the spacing, placement, scale, orientation,
proportion, and size of window and door openings in new
structures to be compatible with the surrounding
buildings that contribute to the historic district, while
reflecting the underlying design of the new building.
.2 Select windows and doors for new structures that are
compatible in material, subdivision, proportion, pattern
and detail with the windows and doors of surrounding
buildings that contribute to the historic district.
.3 New structures should use a roof form found uz the district
_ GENERAL~DE~SIG~Nn#GUIj.ZELIr1E5 ~
or on the landmark site.
.4 Porches should be compatible in massing and details to
historic porches in the district, and should be appropriate
to the style of the house.
.5 Dormers should be secondary to the main roof and should
be lower than the roofline. Oversized dormers are
inappropriate.
NEW PRIMARY STRUCTURES
1~ ~
GARAGES & OTHER ACCESSORY
STRUCTURES
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CITY OF BOULDER
LANDMARKS PRESERVATION ADVISORY BOARD ~ C
i
7. GARAGES & OTHER ACCESSORY
STRUCTURES
Accessory structures include barns, sheds, garages, and
outbuildings. Originally accessory structures were used for
storage of equipment, animals, or carriages. Generally, these
structures have been adapted for the storage of cars. In most
cases, accessory buildings were located to the rear of the lot and
accessed by alleys. They were subordinate in size and detailing
to the primary house. Over time they have emerged as
important elements of many lots and alleys in the district.
Efforts should be made to protect the eclectic character of alleys.
Both additions to existing accessory buildings and new
accessory buildings will be evaluated in terms of how they
affect the historic character of the individual site and the district
as a whole. In the past, larger accessory structures have been
allowed than maybe appropriate today.
7.1 Existing Historic Accessory Structures
A primary concern of the Landmarks Baard in reviewing proposed
changes in historic districts is the protection of existing historic
accessory structures and the character of the site and district.
. I Retain and preserve garages and accessory buildings that
contribute to the overall historic character of the individual
building site or the district.
.2 Retain and preserve the character-defining materials,
features, and architectural details of historic garages and
accessory buildings, including roofs, exterior materials,
windows, and doors.
7.2 New Accessory Buildings
New accessory buildings should follow the character and pattern of
historic accessory structures. While they should take design cues from
the primary structure, they must be subordinate to the primary
structure in size, massing, and detailing. AIIey buildings should
maintain a scale that is pleasant to walk along and comfortable for
pedestrians.
Location and Orientation
. I It is inappropriate to introduce a new garage or accessory
building if doing so will detract from the overall historic
GENERAL DESIGN GUIDELINES
aa..,.~.. rte... ~r Qm,..s r
character of the principal building and the site, or if it will ALLEY
require removal of a significant historic building element r - - - ~ ~ r' ~ ~ - ~ ~ - ~ - - - ~ - ~ - t
or site feature, such as a mature tree. i i i
i
.2 New garages and accessory buildings should generally be i i i
located at the rear of the lot, respecting the traditional ! i i
relationship of such buildings to the primary struchire and I I x I
the site. i _ i i
i i i
.3 Maintain adequate spacing between accessory buildings so i i i
alleys do not evolve into tunnel-like passageways. t ' ~ `j i i
x ~ ,
" I
.4 Preserve a backyard area between the house and the i i i
accessory buildings, maintaining the general proportion of i i i
built mass to open space found within the area. sTREET
7.2.2
Mass and Scale Parking should be provided at the rear
of the lot and accessed by an alley
.5 New accessory structures should take design cues from the whenever possible.
primary structure on the site, but be subordinate to it in
terms of size and massing.
.6 New garages for single-family residences should generally
be one story tall and shelter no more than two cars. In - ~~i
E`, t1 8 ~,t. T',
some cases, a two-car garage may be inappropriate. , ~ k.
,c~_.k- ~ „ '~e
.7 Roof form and pitch should be complimentary to the ' Y '
primary structure. 7.2.517.2.7
Garages should be subordinate to the
Materials and Detailing primary structure and be complimentary
in terms of room form and pitch.
.8 Accessory structures should be simpler in design and
detail than the primary building.
.9 Materials for new garages and accessory stnictures should
be compatible with those found on the primary structure
and in the district. Vinyl siding and prefabricated
struch~res are inappropriate.
.10 Windows, like all elements of accessory structures, should
be simpler in detailing and smaller in scale than similar
elements on primary structures. See Sections 3.7 and 4.5 for
additional direction.
. I I If consistent with the architectural style and appropriately
sized and located, dormers may be an appropriate way to
increase storage space in garages. See Section 3.5 and 4.5
for additional direction.
GARAGES & OTHER ACCESSORY STRUCTURES ~ C
. 12 Garage doors should be consistent with the historic scale
and materials of traditional accessory structures. Wood is
the most appropriate material, and two smaller doors may
be more appropriate than one large door.
. 13 It is inappropriate to introduce features or details to a
garage or an accessory building in an attempt to create a
false historical appearance.
.14 Carports are inappropriate in districts where their form
has no historic precedent.
IOem # C ~ al~~
GENERAL DESIGN GUIDELINES
MISCELLANEOUS
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CITY OF BOULDER
~nda Mem ~ ~ Page # "7 3
LANDMARKS PRESERVATION ADVISORY BOARD
8. MISCELLANEOUS
8. I Paint and Paint Colors
When renovating a historic building, first consider using the original
color scheme. The original paint can often be discovered by careful
analysis of samples of original materials. If it is not possible to discern
original paint colors, a color scheme should be based on historic
precedent within the area. The multiple, bright colors used in San
Francisco, for instance, were not used in Boulder.
Historically, paint colors were more muted tones then those used
today because they depended upon a far more limited source of
pigments. Most wood-clad buildings were painted entirely, generally
with one base color and one or two additional accent colors on details
and trim. For masonry structures, the natural color of the brick or
stone was dominant; paint was applied to wood trim elements around
doors and windows and in gable ends.
As a practical matter, it is suggested that quart samples of the color
scheme should be applied to a section of building as a test before
making final selection. A color on a 1 " x 1 "paint chip will look
different on a whole house.
GUIDELINES
. I Preserve and protect original exterior building surfaces
and site features that were painted by maintaining a sound
paint film on them.
.2 Original materials such as brick and stone that are
unpainted should not be painted.
.3 When repainting, select paint colors appropriate to the
historic building and district. When possible, recreate
historic paint schemes based on samples of original
materials.
¦ When selecting paint schemes, a good rule of thumb is
to use a single body color with a lighter and/or
brighter accent color.
¦ Historic paint colors in Boulder are conservative,
emphasizing muted shades or tones rather than pure
hues. New paint colors should not be bright or garish.
l~gelxie ~011~
~
_P~IIt~
GENERAL DESIGN GUIDELINES
8.2 Energy Efficiency
~tt .,F„ N ~AY NYANe]YF4[ n7iti4 ,t
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j-:In 2006, Boulder's City Council adotited a Climate Action Plan
to meet the Kuoto Protocol Qoals of substantiallu lower emissions of
greenhouse uses. It is the citu's aim to create compatihilitu between
historic preservation and erler~~~ e ~rciencti goals. In the historic
districts and on individualhi landmarked buildings it is important to
ensure that s~--ener e iciencu concerns are addressed in ways that
do not damage or diminish the historic character of the building, site
or district. It is recommended that before anu ener~efficiencu
upgrades are made mr instrumented ener~~ audit is conducted to
determine the building's current energy loss,
In historic districts, a variety of energy-conserving site and building
features illustrate the sensibility of an earlier era to climate and energy
efficiency. Thoughtfully located shade trees buffer residences and
sidewalks from the summer sun. Projecting porches provide shaded
outdoor space and lessen the impact of the harsh sunlight on the
building's interior. Operable windows and shutters allow occupants
to control the introduction of sunlight and breezes within the
buildings. An understanding of how such historic features enhance
energy efficiency is critical to maximizing the energy efficiency of
historic buildings.
For more information re a~~ the energyaudit ~roQram and energy
e ficiencu in historic buildings, tilease contact the O
fice of
Environmental Affairs nt wzvw.environmentala~fairs.eom.
GUIDELINES
. I Retain and preserve the inherent energy-conserving
features of historic buildings and their sites, including
shade trees, porches, and operable windows, transoms,
shutters and blinds.
.2 Increase the thermal efficiency of historic buildings by
observing traditional practices, such as weather-stripping
and caulking, and by introducing appropriate energy-
efficient features, such as storm windows and doors. See
Guidelines 3.7.18 and 3.8.7 for additional direction.
.3 Replace deteriorated or missing wooden blinds and
shutters with matching new units sized to fit the opening.
See Guideline 3.7.16 for additional direction.
MISCELLANEOUS C ~ 75
.4 It is not appropriate to install solar collectors in locations
that compromise character-defining roofs. The installation
of solar collectors located on a prominenty visible roof
ma~~pro~riate provided it does not detract from the
historic character of the property or historic district.
8.3 Mechanical and Utility Facilities
GUIDELINES
. I If a new mechanical system is needed, install it so that it
causes the least amount of alteration to the building's
exterior facades, materials, and site features.
.2 Locate new mechanical equipment and utilities, including heating
and air conditioning units, in the most inconspicuous area, usually
along a building's rear facade. Sc~reeri them from view.
.3 Where possible, locate portable window air-conditioning
units on rear facades or inconspicuous side facades.
Consider noise impacts to neighbors when selecting sites. 'i
.4 It is not appropriate to install ventilators, • ,
antennas, skylights, satellite dishes or other mechanical
equipment in locations that compromise character-
defining roofs, or on roof slopes that are prominently
visible from the street.
.5 Minimize the visual impacts of trash storage and service
areas by screening them from the street.
8.4 Signs
A sign typically serves two functions: to attract attention and to
convei~ information. Signs designed for a historic building should not
detract from important design features of the building. All new signs
should be developed with the overall context of the building and
district in mind.
GUIDELINES
.I Retain and preserve existing historic signs that contribute
to the overall historic character of the building or the district.
.2 New signs should be compatible in material, size, color,
scale, and character with the building.
~ G
GENERAL DESIGN GUIDELINES
.3 Signs should be subordinate to the overall building
composition and in scale with the facade.
.4 Locate a sign on a building so that it emphasizes design
elements of the facade itself. In no case should a sign
obscure or damage architectural details or features.
.5 Supple letter styles and graphic designs are most
appropriate.
.6 A hanging entryway sign may be located on a porch, or
directly above the steps leading to the primary entrance of
a structure.
~penda amp ~~p~
MISCELLANEOUS
8.5 Lighting
Traditionnll y, site lighting was very limited in residential districts.
While today there is typically a need for more lighting and higher
levels of illumination, both building lighting and site lighting should
respect the quality of lighting that characterizes historic residential
districts. When selecting specific fixtures and locations, it is also
important to consider the impact of site lighting on adjacent
properties.
GUIDELINES
. I Retain and preserve exterior lighting fixtures that
contribute to the overall historic character of a building,
site or district.
.2 It is inappropriate to introduce or eliminate exterior
lighting fixtures if doing so will detract from the overall
historic character of the building, site, or streetscape.
.3 Lighting should be functional -not just decorative.
.4 Lighting in alleys should be low wattage and focused
downward.
.5 It is inappropriate to illuminate the facades of houses in
residential districts.
8.6 Artwork
Artwork includes, without limitations, paintings and sculptures,
whether attached to a building or freestanding.
GUIDELINES
.I Retain and preserve artwork that contributes to the overall
historic character of a building, site or district.
.2 Artwork should be subordinate to the overall building.
.3 Artwork should not obscure or damage building elements
or detaiLS. For instance, a mural should not cover windows.
.4 Artwork should not permanently alter the building or site,
such as paint on unpainted masonry.
.5 Artwork should not detract from the historic character of
GENERAL DESIGN GUIDELINES
w..r~ - -1A
the building, site or district, nor should it confuse the
public regarding the period of significance of the building
or district through anachronistic images or details.
8.7 Public Improvements
Public improvement features such as street lighting, street and alley
paving, tree planting, parks, and sidewalks all contribute to the
historic character of a historic district or site. Any public
improvement undertaken by the City of Boulder shall be reviewed by
the Design Review Committee of the Landmarks Preservation
Advisory Board. See Sections 2.3 Allei/s and 2.5 Sidewalks for
additional direction.
GUIDELINES
.I Any public improvement should maintain and reinforce
the character of the historic district.
8.8 Americans with Disabilities Act
Places of public accommodation are required to provide access to their
services and programs under provisions of the Americans with
Disabilities Act. In the case of historic buildings, some provision for
using alternative measures exists if the property is historically or
architecturall y significant enough to merit such treatment. When
changes to a building or site are necessary, careful consideration rnust
be given to how the changes enn be incorporated without
compromising the integrity of the historic building, its character-
dcfining features, or its site.
GUIDELINES
. I Provide barrier-free access that promotes independence for
the disabled to the highest degree practicable, while
preserving significant historic feahires.
.2 The appearance of accessibility ramps or elevators should
not significantly detract from the historic character of the
structure.
.3 If the addition of accessibility improvements negatively
impacts significant historic elements, these improvements
should be designed to be reversible.
MISCELLANEOUS AQM1di~f11~ P~~ 7 J
DEFINITIONS
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9. DEFINITIONS
Alignment The arrangement of objects along a straight line.
Balcony A railed projecting platform found above ground
level on a building.
Arch A structure built to support the weight above an
opening. A true arch is curved. It consists of
wedge-shaped stones or bricks called voussoirs
(vu-swar'), put together to make a curved bridge
which spans the opening.
Baluster A short, upright column or urn-shaped support
of a railing.
Balustrade A row of balusters and the railing connecting
them. Used as a stair rail and also above the
cornice on the outside of a building.
Bargeboard A projecting board, often decorated, that acts as
trim to cover the ends of the structure where a
pitched roof overhangs a gable.
Bracket A supporting member for a projecting element or
shelf, sometimes in the shape of an inverted L
and sometimes as a solid piece or a triangular
truss.
Cantilever A projecting beam, girder or other structural
member supported only atone end; used to
support a balcony, cornice, extended eaves or
any other extension to a building or structure.
Column A slender upright structure, generally consisting
of a cylindrical shaft, base, capital, and pillar: It is
usually a supporting or ornamental member in a
building.
Contributing Buildings
Those buildings built during the district's period
of significance that exist in comparatively
original condition, or that have been
appropriately restored, and clearly contribute to
the historic significance of the district. Such
buildings may have compatible additions.
i GENERAL DESIGN GUID/E~LINES
A~el'Idf ~lIII~ C ~ f
Contributing-Restorable Buildings
Those buildings built during the district's period
of significance that have original material that
has been covered, or buildings that have
experienced some alteration, but that still convey
some sense of history. These buildings would
more strongly contribute, however, if they were
restored. Such buildings may have less
compatible additions.
Cornice A projection at the top of a wall or the top course
or molding of a wall when it serves as a
crowning member.
Deck An uncovered platform, usually with wood
decking and railings, that extends from out from
the main face of a building.
Dormer A window set upright in a sloping roof. The term
is also used to refer to the roofed projection in
which this window is set.
Eave The underside of a sloping roof projecting
beyond the wall of a building.
Elevation A mechanically accurate, "head-on" drawing of a
face of a building or object, without any
allowance for the effect of the laws of
perspective. Any measurement on an elevation is
in a fixed proportion, or scale, to the
corresponding measurement of the real building.
Facade The front or principal face of a building, or any
side of a building that faces a street or other open
space.
Gable Building ends above eave level of a pitched or
gambrel roof. In the case of a pitched roof this
takes the form of an angle. The term is also used
sometimes to refer to the whole end wall.
Historic Context
An organizing structure for interpreting history
that groups information about historic properties
that share a common theme, common
geographical area, and a common time period.
GLOSSARY OF TERMS ~
The development of historic contexts is a
foundation for decisions about the planning,
identification, evaluation, registration, and treat-
ment of historic properties, based upon
comparative historic significance.
Historic Integrity
The degree to which a building has retained its
original elements.
Historically Important Window or Door
The feature has retained integrity from the
period of significance and is an integ=ral part of
the historic design or is essential to the
understanding of the architectural type or style.
Human Scale
Human scale refers to the relationship between
the dimensions of a building, street, streetscape
or outdoor space to the average dimensions of a
human body.
Individually Significant Buildings
Those buildings that are considered individually
eligible for the National Register of Historic
Places or for local landmark designation. These
buildings have a special character and historical,
architectural, or aesthetic interest or value in
Boulder's local history.
Interior Energy Panel
Interior energy panels are single pane glass
panels affixed to the interior of historic windows
in order to reduce conductive heat loss and
prevent the infiltration of cold air from outdoors.
They are an option for increasing energy
efficiency without full window replacement.
Landmarks Board
The City of Boulder's Landmarks Board consists
of five volunteer city residents appointed by the
City Council to consider applications and make
recommendations to Council for landmark and
historic district designations and to review
proposed exterior alterations to Landmarks or
within landmark districts.
GENERAL DESIGN GUIDELINEpS~,,
Landmarks Board Design Review Committee
A Committee that consists of two members of the
Landmarks Board and one member of the
Planning Department staff and meets weekly to
review alteration certificate applications.
Molding A decorative band or strip of material with a
constant profile or section designed to cast
interesting shadows. Generally used in cornices
and trim around window and door openings.
Mullion A large vertical member separating two
casements; the vertical bar between coupled
windows or multiple windows; the central
vertical member of a double-door opening.
Muntin One of the thin strips of wood used for holding
panes of glass within a window; also call
munnion, bar, sash bar, munton bar. Also, the
central vertical member of a door.
Non-Contributing Buildings:
Those buildings built during the district's period
of significance that have been altered to such an
extent that original historic elements are not
interpretable, and restoration is not possible, also
buildings erected outside the period of
significance that are not individually significant.
Non-Historic Window or Door:
Windows or doors that have been replaced, or
are so extensively altered that they are
inconsistent with the pattern,~roportion or
materiality of the historic window or door.
Non-Historic windows and doors maw
retrofitted or replaced. However, the character of
the retrofit or replacement should be compatible
with the historic character of the building (See
Section 3.7.151.
Parapet A low wall or protective railing; often used
around a balcony or balconet, or along the edge
of a roof.
Period of Significance
The time period during which the majority of
GLOSSARY OF TERMS
p ~11~~~~~d-°~
contributing buildings in a historic district were
constructed. The period of significance is
generally established by the designating
ordinance for a district.
Pitch The slope of a building element, typically
expressed as the ratio of vertical rise per
horizontal run, e.g,. a 3/12 pitch indicates a rise
of 3" for every 12" of horizontal run.
Plate Height The distance between the foundation or the
topmost horizontal piece of framing at the top of
a wall and where the next floor framing begins or
where the roof form starts.
Post Apiece of wood, metal, etc., usually long and
square or cylindrical, set upright to support a
building, sign, gate, etc.; pillar; pole.
Primary Elevation
The front or principal face of a building or any
side of a building that faces a public right of wav
or other important public space such as a park.
Tvn~ ieall~, the facade of a building is the most
prominent elevation and will contain character
defining doors and/or windows.
Protection The act or process of applying measures
designed to affect the physical condition of a
property be defending or guarding it from
deterioration, loss or attack or to cover or shield
the property from danger of injury. In, the case of
buildings and structures, such treatment is
generally of a temporary nature and anticipates
future historic preservation treatment; in the case
of archaeological sites, the protective measure
maybe temporary or permanent.
Retrofit In a rehabilitation project, the installation of new
materials into an existing fabric. For example, a
retrofitted window would be the installation of
new glass (i.e. low e glass) that is fitted into an
existing window sash.
Roof The top covering of a building. Some types:
Gable roof has a pitched roof with ridge and
vertical ends.
GENERAL DESIGN GUIDELINES
Gambrel roof is a variation of a gable roof, each
side of which has a shallower slope above a
steeper one.
Hip roof has sloped ends instead of venc~al ends.
Shed roof (lean-to) has one slope only and is built
against a higher wall.
Jerkin-head (clipped gable or hipped gable) is
similar to gable but with the end clipped.
Sash A window component: see window parts.
Secondary Elevation
T~ically a side of a building that has less~ublic
visibility, and may have fewer significant
character defining features than on the facade.
Siding The narrow horizontal or vertical wood boards
that form the outer face of the walls in a
traditional wood frame house. Horizontal wood
siding is also referred to as clapboards. The term
"siding" is also more loosely used to describe any
material that can be applied to the outside of a
building as a finish.
i
Sill The lowest horizontal member in a frame or
opening for a window, door, or framed wall or
partition.
Simulated Divided Light Window
Windows that have muntins affixed to the inside
and outside of the panes of glass to simulate the
look of a true divided light window.
Soffit The underside of a structural part, as of a beam,
arch, etc.
Tertiary Elevation
The side of a building that ty~icall~ has little or
no visibility from the~ublic street and is usually
located at the rear of the building.
True Divided Light Window
Windows that use muntins to form multiple
individual panes of glass in the sash.
Vernacular Buildings in indigenous styles constructed from
locally available materials following traditional
GLOSSARY OF TERMS
building practice and patterns and not
architect-designed.
Ve Historically Imaortant Window or Door
A window or door that has retained substantial
integrity from the period of significance and is
characterized by at least one of the following'.
1. Defines the architectural type or style of
the building and without it the
architectural signnificance would be lost.
2. Is constructed of a rare or unusual
material that would be difficult or costly
to replicate (i.e. stained or leaded lg ass1.
3. Was executed with a hi_~h de r,,
craftsmanship that would render its
restoration difficult or costlt.
4. Conveys artistic merit through skillful
integration of design, material, and color
which is of excellent visual duality.
5. Demonstrates superior craftsmanship or
is an example of the uncommon through
elements of architectural design, details,
or craftsmanship that are representative
of a significant innovation.
Visual Continuity
A sense of unity or belonging together exhibited
by elements of the built environment because of
similarities among them.
Window Condition
Class I: Small repairs, which are usually
performed as part of a building's annual
maintenance program. This may include
paint removal, re- lgazin~, weather-
strippin~, caulking, and repainting
Class II: Shows a small de .
r,.
r~physical
deterioration but can be repaired in place
b~nat~ ,~rproofing
consolidating., or re-gluing. existing
material.
Class III: Localized deterioration in specific areas
that can be removed and replaced
without rec~uiring_a full feature
replacement.
Class IV: Damage beyond repair, including a
completely rotted window sill, wa
~g
or a combination of Class III repairs.
GENERAL DESIGN GUIDELINES
Window and Door Replacement Aanlication and Survey
An ao~lication & survey which must be
submitted as part of a Landmark Alteration
Certificate for the replacement or retrofit of a
window or door on a historically desi n
buildin .The application and survey outline the
methodolo~v used to identify the conditions
location and historic significance of the window
or door and is used to determine if replacement.
retrofit or repair is agpro rp iate.
Window Parts
The moving units of a window are known as
Sashes and move within the fixed Frame. The Sash
may consist of one large Pane of glass or may be
subdivided into smaller panes by thin members
called Muntins or Glazing Bars. Sometimes in
nineteenth-century houses windows were
arranged side-by-side and divided by heavy
vertical wood members called Mullions.
Head Jamb
Rail
i
Interior
Casing Brickmould
Upper Sash
Parting Stop
files
Check Rail I - _
~i
Lower Sash
I ~ Blind Stop
;I
Interior Stop
Stool
untins
Apron ~j
Side Jamb
Sill
GLOSSARY OF TERMS ~~'~®v
Attachment B
CITY OF BOULDER
CITY COUNCIL AGENDA ITEM
MEETING DATE: January 16`h, 2007
AGENDA TITLE: Consideration of a motion to provide direction as to whether
property owners should be allowed to replace rather than preserve historic windows and
on measures proposed to integrate the city's historic preservation and environmental
sustainability goals and guidelines.
PRESENTERS:
Ruth McHeyser, Acting Planning Director
Susan Richstone, Acting Long Range Planning Manager
James Hewat, Historic Preservation Planner
Elizabeth Vasatka, Environmental Sustainability Coordinator
Jim Gery, Residential Plans Examiner
Chris Meschuk, Historic Preservation Planner
EXECUTIVE SUMMARY:
The City Council reviewed the findings from the Historic Preservation and
Environmental Sustainability Integration project on July 18a', 2006. At that time three
options (A through C) outlining approaches to the repair and replacement of historic
doors and windows were presented to the Council which are sutnmarized in Attachment
A. City Council continued the public hearing in order to provide staff with additional time
to further investigate the implications of adopting changes to the city's policy regazding
the replacement of historic windows and doors on designated buildings. In particular, the
Council requested that staff clarify the impact that adopting Option B might have on the
city's Certified Local Govemmentt status and modify Option B accordingly. As
originally presented, Option B proposed evaluating the appropriateness of limited
replacement of historic windows and doors solely on the basis of which elevation of a
building a window or door is located.
On August 3rd, 2006, historic preservation and environmental affairs staff met with
Joseph Saldibar and Amy Pallante, historic preservation architects with [he Colorado
Historical Society, to clarify what aspects of Option B might be might be inconsistent
with the Secretary of Interior's Standards for Rehabilitationz. Based upon this meeting,
~ A certified local government refers to a community that has met special requirements set by the Colorado
HistoricaLSocietysnd the National Park Service, and is authorized to administer a local historic
preservation program and associated activities.
3 The Secretary of the Interior's Standards are the federal standards for historic preservation rehabilitation
in the United States. p 9
AGENDAITEM# C PAGE_~._
staff has made revisions to Option B which it considers will be consistent with the
Standards and will not jeopardize the ci'ty's Certified Local Government Status.
Staff has also explored other potential historic/ environmental conflicts, for example,
regarding historic doors and solar collectors on historic buildings. The Landmazks
Preservation Advisory Board and Environmental Advisory Board (EAB) have worked
together to identify a suggested policy direction on all of these issues as described in
Additional Guideline Revisions on pages 7 & 8 of this memo.
In November of 2006, the Landmarks Board and Environmental Advisory Board each
reviewed and commented on the revised Option B in a public hearing. While neither
Board opted to make a motion to amend their April 26a', 2006 recommendation of Option
A, both Boazds expressed general support of the proposed revisions to Option B. In
general the revised Option B is similaz to the current process for determining which
windows and doors on historic buildings should be preserved and which may be replaced.
However, this option provides for the development and implementation of cleaz and
objective administrative regulations for the Landmazks Boazd and staff to use in the
assessment the relative historic significance and condition of existing windows on
designated historic buildings.
STAFF RECOMMENDATION:
Staff recommends that the City Council adopt revised Option B and direct staff to:
1. Modify the Historic Preservation Guidelines and Green Points Guidelines to:
a) Require property owners to preserve rather than replace significant historic
windows on designated buildings unless deteriorated beyond repair (see below).
b) Encourage property owners to rehabilitate and weatherize historic windows by
weather-stripping and installing additional glazing.
c) Develop and implement cleaz and objective administrative regulations for the
Landmarks Board and staff to use in the assessment the relative historic
significance of existing windows on designated historic buildings.
d) Allow replacement of windows deteriorated beyond repair; deterioration to be
determined by a standardized evaluation of window condition (to be developed
by staff and the Landmarks Board).Replacement windows should replicate the
material, design and dimensions of the original as closely as possible.
e) Encourage the installation of storm windows that match the materials,
proportions and profile of the underlying historic window as closely as possible.
f) Encourage solar collectors and skylights to be placed in inconspicuous
locations, however, as new solar collector technologies emerge with less
noticeable collectors, more flexibility should be given to solaz collector
placement.
g) Allow shutters where there is historic precedent.
2. Produce a brochure that outlines techniques to make historic buildings
more energy-efficient.
AGENDA ITEM # ~ PAGE
3. Evaluate options for the city to take more proactive measures to improve
the energy efficiency of historic buildings, and discourage the demolition of historic
buildings and removal of historic building materials.
(All considered options can be found in the Options Matrix in Attachment A)
4. Work with the Environmental Advisory Board and Landmarks
Preservation Advisory Board to revise the Historic Preservation and Green Points
guidelines to resolve other historic preservation/ environmental sustainability issues
identified by the project. Potential revisions are summarized in Part 2 of the Analysis
section.
COUNCIL FILTER IMPACTS:
• Economic: Individual property owners can benefit from state tax credits for
rehabilitating a historic property. Taking steps to conserve energy can save money
and be an economic benefit to building owners. The tax credit program requires
that work be consistent with the city's historic preservation guidelines design
guidelines and the Secretazy of the Interior's Standards for Rehabilitation.
• Environmental: Conserving energy has important social benefits as the city works
toward compliance with the Kyoto Protocol and Boulder Climate Action Plan.
The city has also identified the protection of important buildings, sites, and azeas
of the Boulder as an important community value. On the other hand, a negative
impact of the historic preservation program is that steps taken to increase energy
conservation that will have an exterior impact on a building, requires review for a
landmark alteration certificate. Boulder's historic preservation program
encourages the reuse and repair of as much of the original building as possible
when making exterior alterations. This project identified several environmental
concerns including the fact that older, poorly insulated and poorly sealed
buildings can waste a lot of energy. On the other hand, preserving and
rehabilitating rather than replacing historic building materials can reduce waste
and raw material use. This project has attempted to weigh and arrive at a
reasonable balance between environmental and historic preservation goals.
• Social: The Historic Preservation Ordinance was adopted to "...enhance property
values, stabilize neighborhoods, promote tourist trade and interest, and foster
knowledge of the city's living heritage." 10-13-1 (a), B.R.C., 1981. The primary
beneficiaries of historic tax credits aze the property owners of a historically
designated building and adjacent neighbors, both of whom aze ensured that the
character of the azea will be protected through the tax credit review process.
OTHER IMPACTS:
• Fiscal: Publishing a brochure on energy efficiency in historic buildings is the
major fiscal impact of implementing [he project. Staff has begun work on the
development of the brochure with funding from Environmental Affairs and
estimates its cost to be approximately $3,000.
• Staff time: Any changes to policies and guidelines can be processed as part of the
normal work program for Office of Environmental Affairs and Historic
Preservation staff. Producing a brochure and evaluating proactive measures to
improve the energy efficiency of historic buildings and discourage the demolition
AGENDA ITEM # ~ PAGE ~I
of historic buildings will require additional resources in the form of staff time or
consultant services.
BOARD AND COMMISSION FEEDBACK:
On November ls`, 2006, the Landmarks Board reviewed and commented on revised
Option B. Whi]e the Board did not make a motion to amend [heir April 26`", 2006
recommendation that the City Council adopt Option A, they did comment that they were
generally supportive of revised Option B stating that it comes closer achieving the
Board's goals of historic preservation and energy conservation than did the original
Option B. The Board also commented that if direction was given by the City Council to
pursue a policy change based on Option B, its successful implementation would rely on
the development and adoption of clear, concise, and fair administrative regulation by the
Boazd.
On November 16`h, 2006, the Environmental Advisory Board (EAB) also reviewed and
commented on the revised Option B. In general the EAB was also supportive of the
revisions to this option finding that looking at each building as a whole when assessing
the historic significance of windows in doors a good thing and represents a less piecemeal
approach than presented in the original Option B. While not amending their motion, the
EAB expressed general support of revised Option B.
PUBLIC FEEDBACK:
No public comment was given at either the Landmark Boazd or EAB's review of revised
Option B. Revised Option B has been distributed to the Ad Hoc committee and identified
stakeholders. Staff has received a letter from Historic Boulder Inc. expressing support for
staff's recommendation (Attachment C) and a letter from Rose Mary Highman requesting
more latitude be given to owners of historic buildings to replace windows and doors
(Attachment D). See (Attachment F) for a summary of the feedback from the Public
Forum.
ANALYSIS:
1. Effect adopting original Option B would have on the City's Certified Local
Government (CLG) Status.
The city's historic preservation program is certified as implementing a program that is
generally consistent with the Secretary of Interior's Standards for the Treatment of
Historic Properties. These include standards for historic preservation and rehabilitation,
which specify that, "The historic chazacter of a property will be retained and preserved.
Distinctive materials, features, finishes, and construction techniques or examples of
craftsmanship that characterize a property will be preserved. The removal...or
replacement of intact or repairable historic materials or alteration of features...that
characterize a property will be avoided. Deteriorated historic features will be repaired
rather than replaced."
On August 3`', 2006, city staff from historic preservation and environmental affairs met
with Joseph Saldibar and Amy Pallante, historic preservation architects with the Colorado
Historical Society, to clarify what aspects of proposed Option B might be inconsistent
with the Secretary of Interior's Standards for Rehabilitation. r
AGENDA ITEM # PAGE ~ "
Saldibar and Pallante explained that the Standards for Rehabilitation are the nationally
recognized set of guidelines upon which most historic preservation programs are based.
In Colorado there are thirty-eight communities that employ the Standards through the
Certified Local Government program, and over 1200 communities nationally have
programs that use them. The Standards aze neither technical nor prescriptive, but are
intended to promote responsible preservation practices that help protect important
cultural resources. For example, they cannot, in and of themselves, be used to make
essential decisions about which features of a historic building should be saved and which
can be changed. But once a treatment is selected, the Standards provide philosophical
consistency to the work. Saldibar and Pallante consider the approach of choosing
windows on a building based upon which elevation they aze located (original Option B) is
philosophically inconsistent with the Standards.
The Secretary of the Interior's Standards were originally published in 1977, and revised
in 1983, 1990, and 1995 as part of Department of the Interior regulations (36 CFR Part
67, Historic Preservation Certifications). They pertain to historic buildings of all
materials, construction types, sizes, and occupancy and encompass the exterior and the
interior of historic buildings (the City of Boulder's historic preservation program has no
purview of the treatment of a building's interior). There aze currently no plans to revise
the Standards, though technical information in the form of Preservation Briefs and
Technical Notes aze regularly published by the National Park Service and intended to
supplement the Standards as preservation technology evolves. The Standards also
encompass related landscape features and the building's site and environment as well as
attached, adjacent or related new construction.
Saldibar and Pallante consider that Option C, which allows replacement of all historic
windows, would be inconsistent with the Standards and would threaten Boulder's CLG
status. The same is true of Option B, as originally presented, as it determines the
appropriateness of limited replacement of historic windows and doors on the basis of
which elevation on a building a window or door is located. Under this option any window
could be replaced on a tertiary elevation while no windows could be replaced on a
primazy elevation. Saldibaz and Pallante point out that this "elevation based" approach
fails to take into consideration the importance of looking at each building as a whole and
the possibility of unique circumstances under which such an application might conflict.
For instance, there may be circumstances where a contributing building in a historic
district or an individual landmark may contain important character defining features on a
tertiazy elevation. Likewise, non-historic windows may exist on the primary elevation of
a designated historic building which could not be replaced under Option B, as originally
presented.
2. Revisions to Option B based upon comments from Colorado Historical Society.
The proposed revisions generally reflect current historic preservation practice and
provide for consideration of the replacement of windows and doors on primary,
secondary, and tertiary elevations of a building based upon their significance to the
historic character of the building. This revised option offers more flexibility by
approaching window replacement on acase-by-case basis while taking into consideration
the importance of looking at each building as a whole. p.
AGENDA ITEM # ~ PAGE 7.~
Specifically, the revisions to the elevation based approach are:
- Primary elevations ("front") - in most cases windows and doors must be
preserved, should be rehabilitated and fitted with a storm system to
improve energy efficiency on these elevations. If windows aze non-historic
(less than fifty years in age) they may be replaced with energy efficient
windows that closely replicate what were on the building historically.
- Secondary elevations ("side") - in most cases windows and doors should
be preserved and should be rehabilitated and fitted with a storm system to
improve energy efficiency. Limited replacement may be appropriate based
upon the historic character and value of windows and their public
visibility. If windows or doors are non-historic (less than fifty years in
age) they may be changed out with energy efficient replacements that
closely replicate what were on the building historically.
- Tertiary elevations ("rear") - in most cases windows and doors may be
changed out with energy efficient replacements. If windows or doors are
deemed to impart exceptional chazacter or value to the building they
should be rehabilitated and fitted with a storm system to improve energy
efficiency. '
• Character and value of windows and doors would be assessed on a case-by-case
based (with specific criteria for determination developed by staff and adopted by
the Landmazks Board as administrative regulation);
• An additional insulating layer of glazing, such as a storm window (or door) or a
second interior pane, is encouraged on inefficient historic windows. Exterior
storm windows (or doors) should match the material, proportions, and profile of
the underlying window or door as closely as possible.
• Historic windows (or doors) if deemed deteriorated beyond repair, may be
replaced. Approval of a replacement would be based on a formal evaluation of
the window (or door) condition deterioration against criteria developed by staff
and adopted by the Board. This could be a form filled out by the homeowner and
submitted with photos for review by staff.
• Any replacement of a historic window (or door) should replicate the material,
design, profile and dimensions of the original as closely as possible.
• Solar collectors and skylights are allowed on more visible elevations of a
building.
• Shutters may be allowed on primazy, secondary, and tertiazy elevations if there is
historic precedent.
The main disadvantage of adopting revised Option B would be the increased amount time
needed for case by case review for the replacement of historic windows and doors.
Implementation of this policy would require the development of standards to assess the
historic importance and relative conditions of historic windows and doors. It could add
time to the review/ approval timeline for a Landmark Alteration Certificate (currently
approximately one week) (For context, the total review/ approval timeline for a remodel
or addition project that requires an alteration certificate as well as a building permit is
about 6-10 weeks.) A comparison of the revised Option B in relation to options A & C is
in Attachment A.
AGENDA ITEM # C PAGE
Staff considers that revised Option B provides a more reasonable compromise between
the preservation and replacement of windows and doors on historic buildings; and one
that is more consistent with existing historic preservation philosophy. A letter from
Colorado Historical Society historic preservation architect Joseph Saldibar endorsing the
revisions to Option B is in Attachment B.
3. How does revised option B differ from the original option B reviewed by City
Council in July?
The revised Option B provides for consideration of the replacement of windows on
primary, secondazy, and tertiary elevations of a building based upon their significance to
the historic character of the building. This revised option offers more flexibility by
approaching window replacement on a case-by-case basis while taking into consideration
the importance of looking at each building as a whole.
The original recommendation was based primarily upon the visibility of the elevation
where the windows (or doors) aze located (and on the historic value of the window or
door on the secondary elevation). The objective of this option was to offer property
owners flexibility to replace windows for energy efficiency or other personal reasons
where less historic significance is at stake, while being more protective of windows
where more historically significant. This option is based on the finding that rehabilitating
and retrofitting historic windows with a storm window or second pane approaches the
energy efficiency of a new double-pane window, but, by allowing some window
replacement, acknowledges that new window technologies, which aze currently only
recommended for new insulated panes, can take energy efficiency a step farther.
Revised Option B Recommendation '
Staff considers that the revised Option B is ad improvement over the original Option B in
that it approaches the building in question in a more holistic manner in assessing when
the preservation or replacement of windows and doors is appropriate in a manner that is
more consistent with existing historic preservation philosophy.
One disadvantage of this option is the extra level of time required to determine historic -
significance of windows and doors, elevation hierarchy, and relative condition of
windows proposed for replacement. It could add time to the review/ approval timeline
for a Landmark Alteration Certificate (currently approximately one week). (For context,
the total review/ approval timeline for a remodel or addition project that requires an
alteration certificate as well as a building permit [with or without a Green Points
requirement] is about 6-]0 weeks.)
At the Apri126, 2006 joint meetings of the EAB and LPAB, the boards both opted for
Option A. The majority of board members stated that they considered the difference in
energy efficiency between Options A and B wasn't great enough to justify allowing the
removal of historic resources, particulazly if property owners are encouraged to weather-
stripand add an additional layer of glazing, such as a storm window or second interior
pane. There seemed to be agreement that on a broad environmental perspective allowing
windows to be replaced on the small percentage of designated histo/rlic buildings whose
AGENDA ITEM # C PAGE
owners might consider new windows (currently less than 2% of the buildings in Boulder
aze designated historic) will not make a notable difference in reducing city-wide
greenhouse gas emissions.
Additional Guideline Revisions
In addition to the window/door replacement and solar collector/shutter/skylight issues
addressed above, staff explored other potential conflicts and gaps concerning the city's
Historic Preservation and Green Points programs. Staff sees a need for the Green Points
Guidelines to acknowledge the city's Historic Preservation Program and the
environmental benefits of preservation and rehabilitation. Also, staff heazd from the ad-
hoc panel that there is a need to better educate property owners, prospective homebuyers,
building professionals, and the public about values, benefits, and responsibilities of
historic preservation. In addition, staff, the ad hoc panel, and the two boazds agreed that
the city should better educate property owners on the many ways to improve the energy
efficiency of historic buildings. Staff proposes revising the Green Points and Historic
Preservation guidelines to address these needs.
Potential guideline revisions to the Green Points Guidelines could include:
• Adding a section about the Historic Preservation Program goals and principles, how it
complements the Green Points Program intent to conserve resources, and how the
Green Points Program applies to historic buildings and the alteration certificate
process.
• Adding Green Point options for:
Rehabilitating a historic house
Installing storm windows and doors and/or second pane to existing single pane
Repairing, sealing and weather-stripping existing windows and doors
Donating historic building materials to salvage businesses
Installing automated, operable shutters
• Adding sidebar information on: replacing historic roofing materials (tile, slate); the
energy benefits of shades, blinds, curtains; and tax credits available for historic
rehabilitation.
Potential revisions [o the Historic Preservation Guidelines could include:
• Adding sections on:
The benef is and responsibilities of historic property ownership
Historic preservation principles used for evaluating historic resources, including
windows
How to improve the energy efficiency of historic/existing buildings
A list of allowed window treatment options with pros, cons and energy
information.
Where to find information/ regulations on tempered glazing, egress, lead and
asbestos hazards and abatement for historic/existing windows
• Amending guidelines to provide more specificity on:
Appropriate design and materials for replacement windows, doors,
siding, and roofs p.
AGENDA ITEM # n PAGE l~
How tfie window/door guidelines apply to accessory buildings
Recycling and re-using historic materials
No conflicts or gaps were identified regarding any other historic preservation and
environmental sustainability goals, standards or guidelines, other than to consider adding
"environmental sustainability" to the Boulder Valley Comprehensive Plan policy on
coordinating multiple city goals in developing a Boulder Valley-wide preservation plan
(Policy 2.35).
BACKGROUND:
An ad hoc panel of five experts in energy efficiency, sustainable building, windows and
historic preservation was assembled for the project in eazly 2006 to assist staff with the
analysis of technical information on energy efficiency in historic windows and assist with
the development of policy options (see Attachment F, "Ad Hoc Panel Members"). The
Ad-Hoc committee met twice to identify common ground and conflicts between the city's
historic preservation and environmental sustainability policies, programs, guidelines and
regulations, and propose changes where needed to resolve conflicts and fill gaps.
Although not charged with recommending a particular option, at its meeting the panel
indicated that they were leaning towazd Option B.
A public forum was held on March 13, 2006. At the forum the panel members were
asked what key conclusions they had drawn about replacing vs. rehabilitating historic
windows for energy-efficiency purposes. Public input on the policy options and other
project information was gathered mainly through the public forum and the project Web
page. Almost 30 people attended the forum. The forum included informal one-on-one
discussions with staff and a formal Q & A session with the ad hoc panel. Eight people
returned the comment form that was handed out. The forms showed a neazly even split in
support of Option A or Option C. Only one favored the original Option B. Another
proposed an Option D, which would allow window replacements but be stricter on solaz
panels.
At their joint meeting on April 26, 2006, the EAB and Landmarks Board each voted
unanimously to recommend Option A to the City Council, the option most protective of
historic windows, with several amendments as listed in the executive summary. Option B
was formulated to allow the replacement and preservation of historic windows, based on
the historic significance and visibility of the elevation where the windows aze located
(and on the historic value of the windows on the secondary e]evation). Option C was
offered as an approach to allow property owners of designated buildings to replace all
historic windows, regardless of their location and significance, with new energy efficient
windows. Staff had recommended Option B as a compromise balancing the needs of both
historic preservation and environmental sustainability. This recommendation was based
upon an exhaustive review of technical literature, public input and the findings and facts
made by the Historic Preservation and Environmental sustainability Integration ad-hoc
committee (see Attachment F).
However, the majority of Boazd members stated that the difference in energy efficiency
between Options A and B wasn't great enough to justify allowing the removal of historic
resources, particulazly if property owners are encouraged to weathe/r~-strip and add an
AGENDA ITEM # PAGE
additional layer of glazing, such as a storm window or second interior pane. There
seemed to be agreement that from a broad environmental perspective, allowing windows
to be replaced on the small percentage of designated historic buildings whose owners
might consider new windows (currently less than 2% of the buildings in Boulder) will not
make a notable difference in reducing city-wide greenhouse gas emissions.
NEXT STEPS
if Council adopts the staff recommendations, staff will work with Landmarks Board and
EAB to:
• revise the Historic Preservation and Green Points guidelines to:
- reflect the policy outlined in Part 1 for historic window and door
replacement and solar collector, skylight and shutter placement, and
- better integrate and educate about the two programs, as referenced in Part
2;
• produce a brochure on improving the energy efficiency of historic buildings;
and ;
• evaluate options for the city to take more proactive measures to improve
energy efficiency of historic buildings and discourage the demolition of
historic buildings and historic building materials as part of the 2007 work
plan.
Approved By:
Frank W. Bruno,
City Manager
ATTACHMENTS:
Attachment A: Comparative Table of Option A, Revised Option B, and
Option C
Attachment B: 10/25/061etter from Joseph Saldibar regarding proposed
revisions to Option B.
Attachrent C: 10 j27/061etter from Historic Boulder, Inc
Attachment D: 11 /09/061etter from Rose Mary Highman
Attachment E: Ad-Hoc Committee members
Attachment F: Findings of the Ad-Hoc Committee
AGENDA ITEM # ~ PAGE / r/
Comparative Table of Option A, Revised Option B, and Option C
Option A: Preserve all Revised Option B: Preservation Option C: Allow
Goal: historic windows based upon importance of window replacement of all
or door to the building as a whole. historic windows
Historic Generally consistent with -Generally consistent with - hlcor~sistent with
preservation Secretary oflrtterior Secretary of h~terior Standards Secretary of Interior
Standards regarding the regarding the preservation of Standards regarding
preservation of character character defining features i.e. the preservation of
defining features i.e. window preservation by evaluatutg character defining
window preservation/ value of windows and doors to the features i.e. window
repair vs. replacement. buildingas a whole, and preservation/ repair
approaching each application on a vs. replacement.
case-by-case basis. -Could jeopardize
- Should zlot jeopardize the city's. city's Certified Local
Certified Local Government status. Governrrient status....
Energy Achieves the least energy .Achieves zrioderate energy Achieves most.
Efficiency efficiency of t11e options: efficiency: energy efficiency:
Allows replacement of -Allows for replacement of non- -New double pane '
non-historic windows historic windows on with windows are more
" withappropriate energy appropriate energy efficient energy efficient than
efficient windows. windows. single pa~1e
Sit7gle pane windows -Single pane windows are not as windows: Those-
~ are not~asenergy efficient energy efficientas double pane with the latest, high-
as double pane windows. windows. performance
" -Special coatings. that -1n most cases, requires character coatings and
improve window ertergy defining windows and doors to be material are more
efficiency -are currently retained. energyefficient than
not available for historic -Repairing, weather-stripping and: single pane
windows and. those that retrofitting historic single-pane windows with storm
` ' can be applied to storm windows with storm windows or windows or added
windows or added panes second panes will sigtificantly pane.
degrade over time. improve energy efficiency,
- Repairing, weather- particularly if windows are leaky. `
stripping and retrofitting _
hstoric single-pane - -
windows with storm
windows or second
panes will greatly
hmprove energy
.
efficiency, particularly if
windows are leak .
Resource Reduces waste and Reduces some waste and Does not reduce
conservation consumption of new consumption of new window waste or
window materials. materials. constunption of new
window materials.
Historic Maintains most authentic -Maintains character-defining Least authentic -
appearance lstoric appearance doors and windows and doors of allowsreplicated
throughout, although historic value although exterior historic appearance.:
exterior storm windows storm windows may reduce public
ma reduce ublic visibilit of historic windows and
AGENUA I'CENI # ___YAGE~_
visibility of historic interior second panes and storm
windows and interior windows will be discernible from "
second panes and storm exterior.. _
windows will be -Non-historic windows and doors
discernible from exterior. may be replaced with energy
efficient re Micas.
Review High level of Lowest level of predictability and,.: High level of
process predictability and consistency, as determinations must;, :;predictability and
predictability consistency, except when be made~based upon character, ~ ~ consistency,
and determination must be historic value, visibility, and level of :although
consistency made about deterioration. deterioration. replacement
:windows must still
be ap~~roved for
historic a earance .
Review Same as current practice, Most complex Simplest, although
process except process for -New requirement for evahtations : alteration certificate'
simplicity deternlining window of character/historicvalue, still regtured for
condition/.deterioration visibiii y, and level of deterioration. replacennents. -
formalized. -Alteration certificate requixed fox
-New requirement for storm windows, addition of second
window condition pane, or replacement ofnon-historic -
evaluation required fqr or deteriorated window or door.
replacement of
deteriorated windows -
Alteration certificate ~ ~ ~
required for storm
wuidows, addition of ~
second pane, ox
replacement of -
deteriorated window.
Review Approximately one week Approximately one-two weeks for Approximately one
process time for alteration certificate. alteration certificate. week for alteration
certificate.
AGENDA ITEM # ~ PAGE ~VV
October 25, 2006
James,
Attached are my comments for the revisions to Option B, part of Boulder's
Environmental Sustainability Integration Project.
On page 4, the idea of historic windows as being inefficient (and of new windows
being energy efficient) is presented several times. I'm concerned that this may
give folks the impression that old windows are naturally inefficient, which is not
entirely true. It also makes it seem as if people are "stuck with" these old
inefficient windows because they happen to be in a certain spot, or of a certain
style.
On the same theme, there is no real definition for what "closely replicate" means
(with regards to replacement windows.) The folks who sell vinyl windows with
the snap-in grids market their products as :closely replicating" historic windows,
but it takes a good imagination (and perhaps some poor eyesight) to believe that
statement. Perhaps an addendum is needed to describe what kinds of features
make a replacement window a "good" replacement or a "bad" one?
f'd also recommend some guidelines for the placement of solar collectors and
skylights on the roofs of homes, particularly when placed on the front elevation
(or other public-viewable area).
Finally, although Option B would increase review time, it does not appear to
substantially increase review times, as noted on Page 7. One Page 6, the
estimated review time is given as "one to two" weeks, just a bit longer than the
one week predicted for Options A and C.
On the whole, however, I think that Option B is very flexible and fair, and
balances the needs of energy efficiency and historic preservation.
Joe Saldibar
Architectural Services Coordinator
Colorado Historical Society
303-866-3741
AGENDA ITEM # ~ PAGE !D'
Historic Preservation and Environmental Sustainability
Ad-Hoc Panel Members
Larry Kinney, Ph.D.
President, Synertech Systems Corporation
Boulder, CO
Chris Koziol, Ph.D.
Professor, Construction Management Dept., Colorado State University
Fort Collins, CO
Kristin Lewis
Owner, Kristin Lewis Architects
Boulder, CO
Victor Olgyay
Principal, RMUENSAR Built Environment Team
Boulder, CO
Mark Wernimont
Owner, Colorado Sash and Door
Fort Collins, CO
AGENDA ITEM # ~ PAGE ~ bZ
ATTACHMENT F
AD-HOC PANEL FINDINGS AND FACTS
Mazch 13, 2006 Public Forum
Findings on Energy Efficiency of Windows
Staff and the project Ad Hoc Panel have made the following findings, based on the
studies and articles gathered and reviewed by staff and the panel (in Baseline Information
binder):
- Weatherization: Repairing, sealing and weather-striping can greatly improve the
energy efficiency of a leaky single-pane window.
-Single-pane vs. double-pane: Double-pane windows lose less heat than single-pane
windows and can keep a house cooler in the summer. At today's energy prices, an
average house in Boulder with single-pane windows would pay approximately
$150-$300 more annually for heating and cooling than a house with double-pane
windows.
-Retrofitted single-pane vs. double-pane: Rehabilitating asingle-pane window and
adding a stotm window or a second pane can result in energy-efficiency close to
that of a new double-pane window.
- Cost/Payback of new: Due to the relatively high cost of new windows, replacing
single-pane windows is razely justified on the basis of energy cost savings alone.
Estimated payback period for new windows is usually several decades.
Additional Facts on Windows
The following facts also come into play in considering options for windows and were
discussed by staff and the Ad Hoc Panel.
- Other factors: Other reasons besides energy efficiency cited for replacing old windows
relate to comfort, operability, condensation, safety, and maintenance.
- Comfort: Discomfort caused by radiant heat loss and drafts from windows is inversely
correlated with window energy-efficiency. In general, the better sealed and
insulated a window, the more comfortable it will be. A poorly sealed, un-insulated
single-pane window will feel less comfortable than swell-sealed double-pane
window or swell-sealed single-pane window with storm window.
- Maintenance: Wood windows require painting, whereas synthetic ones do not. Other
window maintenance is similaz.
' Weatherizing an old window can include:
- -squaring up the frame,
- repairing or replacing rotted parts,
- re-puttying joints between muntins and panes,
- caulking cracks in the frame,
- adding weather-stripping at vertical and horizontal joints on the sash,
- repairing or replacing the lock,
- insulating [he rough opening between [he frame and wall. 11
AGENDA ITEM # PAGE ~f~J
- Longevity and repair: New windows made with insulated glass and wood, vinyl- or
metal-clad wood, or vinyl frame may not have the longevity of historic wood or
steel windows, and may be more difficult to repair:
-New windows usually are warrantied for 20 years or less; windows made 50 or
more years ago can be expected to last at least another 50 years if maintained.
- Vinyl becomes brittle and cracks over time.
-Seals on insulated glass can break and allow condensation in 20-30 years.
- If a simulated divided-light pane breaks, the entize sash, not just the pane,
must be replaced.
- Newer woods are not as strong as 19`"- or early 20`h-century woods. Newer
locks and handles also tend not to be as durable.
- However, wood is more susceptible to moisture damage.
- Fiberglass windows have good life expectancy and seals, but few aze being
manufactured and their profiles aze not as historic-looking.
-Storm window installation: If improperly installed, stone windows can cause
condensation and be difficult to operate. The inner-most pane must be sealed more
tightly than the outer pane to prevent condensation.
- Storm window operability: Some storm windows do not allow for operation of the
underlying window and therefore usually aze changed seasonally; others do, and
therefore can stay in place yeaz-round.
- Storm window cleaning: Storm windows may make window cleaning more difficult.
-Shutters: Automated operable shutters hold promise for high energy efficiency for
single- and double-pane windows, however they are not in widespread use. The
availability of models that would fit the character of Boulder's historic districts
needs more reseazch.
- Glass/ sash replacement: If replacing original single-pane glass with new double-pane
glass, it may be advisable to consider replacing the sash instead. Although replacing
the sash would result in a greater loss of historic materials than replacing just the
panes, new sashes have a longer life expectancy and warranty and a more historic
appeazance.
- Skylights: Operable skylights offer not only day-lighting, but also thermal gain and
cooling/ ventilation. However, they also account for substantial conductive losses
during hot periods in the summer and cold periods in the winter.
- Replicas: -Replacement windows that look similar to historic windows are available.
However, in some cases, their materials, glazing, larger part size, and smaller
daylight opening make them recognizable as replicas.
- Permanent color: The color on clad windows can never be changed.
- Tempered glazing: Whether or not the glazing in an existing window is required by the
city building code to be replaced with tempered glazing depends on whether the
window is proposed to be altered and on the proposed window dimensions and
placement relative to nearby doors, stairways, and floor heights.
- Egress: The city building code may require modifications to doors and/or windows to
provide or improve egress if an existing building is re-modeled or expanded.
- Hazardous materials: Any lead paint and asbestos hazards must be mitigated according
to Boulder County Health Department and state regulations, whether a window is
being restored or replaced. Windows that may or do have lead paint should be kept
painted-over or stripped of the lead paint according to established procedures for lead
paint removal, in order to prevent paint chips or airborne lead dust.
AGENDA ITEM #~PAGE
Attachment C
A a r c h i t e c t
City of Boulder
Planning and Development Services
1739 Broadway, 3°r Floor
P.O. Box 791
Boulder, CO 80306
October 19, 2007
Re: Proposed Changes to the General Design Guidelines
Window and Door Replacement and Retrofit Application
Deaz James,
Enclosed are my comments on the draft revisions to the General Design
Guidelines regarding repair, retrofit and replacement ofwindows and doors
on designated historic buildings and the drafr of the Window and Door
Replacement and Retrofit Application.
Please give me a call if my handwritten comments aze illegible or if you
would like to discuss any of my comments in further detail, 303-449-0490.
Sincerely,
Lisa Egger
2455 TENTH STREET
BOULDER, CO 80304
TEL 3 0 3. 4 4 9. 0 4 9 0 -
FAX 3 0 3. 4 4 9. 0 4 8 9
t E~ t I S A E G G E R. C O M
ApNldo Metn#~Papef b5
Draft Revisions to the "General Design Guidelines for Boulder's
Historic Districts and Individual Landmarks".
(Underline indicates new language, strike indicates deleted language.)
1.2 Purpose of the Design Guidelines
A `~Cf
The intent of the design review process is to ensure at prop terations of
Landmazk properties will not adversely affect or d y thei t haracter or
architectural integrity and that all changes are cons the s d p ~ ose of the
Landmazk Preservation Ordinance. The Landmazks adopted th ry of the
Interior's Standards for Rehabilitation as the basis ce on rehab ation design
for historic properties. These guidelines expand those St and bring focus to
Boulder's own historic context and resources. a ideline ded to be used as
an aid to a ro riate deli and not as a c 'terns for c liance.
3.7 Windows, Storm Win s, a S ~rs
Windows, the elements that s them, an ~ relationship to one another are one
of the most im ~at~ter- ' g elements of a historic buildin - and
should be ~ er or r treatment of the windows on a historic
structur n seriously~~ om it itectural character. The relative in:por~tance
r
o a ow de ends on th ctors: location o t window on the buildin tl:e ~e~. ti,,tj
hi i ni cance o the ow and its condition. Windows on facades visible from' yv~t,ke
b r , particul the f~•ertt fagade, are especially important. A window that Sw~S-C
has a hr l o historic i cance re ardless o its location ma a so be very (!a-S~4!
im ortant istoric i ri o tlae buildin .The re lacement o historic windows 4"'Yi
should be con ~ as a last resort. ~ f
s_~,
At times, -property owners consider replacement of their historic windows as a way of
im roving enerav e~ciency. While the ener2y loss of a building may be reduced by
replacing or repairing historic windows, windows pre only one factor in the buildin o's
eneruy usaxe. It is recommended that a comprehensive energy audit be undertaken to
identify areas for improvement. To increase a building's energy efficiency, a
combination ofair sealine additional wall and ceiline insulation, and the adiustmer:t of
mechanical systems is zenerally more effective than focusing only on the repair or
Agarwla IMmf C Prps~
T'
' ~j
r~lacement of u window. For more information reearding energZefficiency and enerrv
audits for historic buildings Dlease contact the Office of Environmental Affairs
GUIDELINES
Protection of Historic Windows
.1 Retain and preserve existing historic windows, including their functional and decorative
features, such as frames, sashes, muntins, sills, heads, moldings, surrounds and hazdware.
Because windows neaz the €tent facade are particularly c ' • the azacter of historic
buildings, their protection may supersede the protectio to doves elsewhere. In
some cases, it may be appropriate [o use window, ele nts from side elevations to
repair those on the front.
.2 Preserve original window locations; move wind their hist acement.
l/W ~ ~ ~ Sft /j~,
f` N°ta'.~itlt'`~~ Q`l^4+~ ? -~`il"A~,t~'~ l"ni6'~.~
.3 Repair rather than replace the~functional and decorative featur ti ' windows /e~avtc
through recognized preservation methods. If ent of a fe s necessary, replace ~~..~°1'~"ti"6a
only the deteriorated feature in kind rather nth unit, m ing the materials,
design and dimensions of the original. °i '
~,,r
't
Retrofit of Historic Windows ~E ~
.4 In some cases r 'tonic s- to make them more ever efficient ma be
a ro riate o •ehabr o . T icall a window retrofit
reserves. °'st or all of [he• •c woo ass or metal com onents and consists of
insula ' " wei ht ockets an lete Bather stri in of its sash and frames. If a
~~a
wi •ofit cal]s for the re ement of sin le ane ass it is im ortant to determine
thdt the ~ • ill not com ro the historic character of the buildin or the dishict in
which it is .Historic s is t ified b its "way "uneven surface which can be an
im ortant cha efinin eature of a window and the historic buildin as a whole.
De endin¢ u on`ir ` on [he buildin the im ortance to the window itself and
relative condition, t placement of historic glass may be inappropriate.
• Retrofitting historic true divided light windows with thermal-pane glass is inappropriate
nn primaiv or secondary elevations.
• Retrofitting historic windows on primaryelevations is rarely appropriate unless the
glass has been replaced with non-historic Glass.
• The dimensions and relationship of replacement Blass to the stiles, rails, and muntins
must closely match those of the unimproved window:
• The retrofit of historic sash with visibly tinted or reflective Blass is inappropriate.
• The introduction of weather snipping, insulation, or materials to improve the operation
of historic windows must not be visible from the exterior of the buildin¢.
AgNMl~ Nstti_~Paps* ~ D~
i
Window Replacement
5 The repair of historic windows and doors is always preferred as part of a rehabilitation
proiect Research indicates that, inmost cases, the enerey efficiency of an old window can
be increased to that of a thermal pane replacement by weather-stripping, insulation of
weight pockets and the application of an interior or exterior storm system. However if the
ro ert owner wishes tore nest a landmark alteration ce to lace windows on a
contributin or individual) landmarked >buildi st outlined in the
Historic Window and Door Re ]acemendRetrofit Gu' elines m )lowed.
:4 >
.6 The location of the windows ro osed for retrofit or re lace i octant in assessing
their si ificarice to a historic buildin . In en more im he elevation where
the window is located the less like) that re t cement be a ro riate.
Elevations will be cate orized as rima -and 'a usin the methodolo set
out in the Window & Door Re lacem A c n an e .
~'~s.
• Re lacement of intact histo ' ndows on levations is rare) a ro riate.
• Re lacement of intact hist ows on sec` elevations is enerally
ina ro riat "~"zy_~ s
• Re lace $ rfl 'c win ~ertiar elevations can occur rovided it
does 'com romise t ric int of the buildin .
} >
.7 The piston ' tcance oft indows ro osed for re lacement must also be assessed.
In general th si ifi t a window is to the buildin as a whole the less like] that a
retrofit or re lac e a ro riate. The a ro riateness of a window re lacement O
will be determined rt based upon characterization of the window -as either `Very
Historically Import~f' `Historically Important' or `Non-Historic' (See Defimttons).
TM .7 1F ti 1.7 ti f .I7.... .n.~lI 1, 1.] ....,ae 7.,.-..o..
' r b ' , r,•ucn
8 The condition of the window -must be evalulted prior to determining whether the window
or door may be repaired or replaced The condition is to be determined by'assessinQ its
elements individually The assessment -must be completed through the use of a survey that
identifies the extent of deterioration in each window and determines whether the windows
map be repaired retrofitted or replaced The survey form documents the existine condition
for the window and identifies which features will be repaired and which will possibly be
replaced. ~,y . !t ;~rjv!~ .F-'( ~"/~VV_~'".~ ~ - ~ C~G,~°}.l ~%`';;f .
®`iiV1~/V 1/'~ ~ .r~f~~~ 7 , ~'Y l-;c~, (c~ u`ia~ f~'l~.~rl<'~t~t..5
r
a- i' tJ/~ G. 'i ~ _ ~t~''v Lrfi"Y1c`.. -fit., (1/_>,7/t/' lal
..o e.,.....«
..te ..1.. .I.e :ae va ;F rl,o «.u.., .i:.,, ..F.lo ed~;«.l}. :1.,
mnJ ___-1 _a rC_____
.9 If, throu¢h the Window & Door Aaylication &Survev, it is determined that the window
sashes are too deteriorated to repair (Class III & IV), but the window frames are
salvageable, then sashes only should be replaced to match the original per the Retrofit or
Reylacement Section.
4 TF :«A..... ?6.a A:..:AeA ~e..e.-.,7 .,.,«e....F ,.1 ,,.....«....f l,e ..e,.7,..,eA ~:,«:1.,~ f~,.e
r~___ a____ __r_____,
_ C.t
.10 If throu the Window & Door A lication & Survev`°" ~ [ermine i W w ma be
re laced Class III & IV the window o enin itself sh ~ carefull ed. It
should not be made lar er or smaller to accommodates
di sized window.
• o •
.11 If throw h the Window & Door A li 1ti S ~ ve 1 termined the window may be
re laced Class III & fV the same 'al as the i nal is most a ro iiate•
however other materials ma be idered if t s ~ ion dimension iofile and finish
are the same. - "
~ t,T
~ t. i. ,
.12 ff a windo is divided in veral anes of lass must be re laced a similar tme-
divided-li ht w that hes the dimensions rofile and detailin of the on final is
most a ro riat rt simulated-divided-li ht windows ma be allowed if the
maintain the munt f the original window. Sna -in muntins or other inauthentic
architectural details ina ro riate.
~xr.:d~.. ~ti,. ,la T,e va . :«l. ..«e 1.. a., ..le F:« ,.w and
.13 Historic steel windows are character-defining features on some buildings in historic
districts. Because windows manufactured from other materials generally cannot match the
thin profiles of steel, replacement may not be appropriate.
cpc.....a., ,
.14 If the existin¢ condition of the window(s), as documented by a Window & Door Survev.
indicates Class III or IV damage or deterioration, then the window(s) may he retrofitted or ,,r]
Aperd9wnn# C p®paf ~l~l
replaced. All retrofitted or replacement windows must match the historic feature as closely
as possible.
Windows in New Construction
c.,....,,e.~., „o,.., „r,,.,o.,: s>~..~a do
.15 Windows in additions and new structures should reflect the window patterns and
proportions of the existing structure and the district and utilize similar materials. For
elevations visible from public streets, the relationship of solids to voids should also be
compatible.
1a~
e b ' 1
~irt~ ~ •P
.16 Windows should be trimmed with materials similar inr ro ortio d
character to those used traditionally.
5
.17 O enin s should indicate floor levels ands `°ul ur betwe~
floors. ~dvV ~ r%r
.18~S~meh• or as mmetr of o e ' A~should be ,~n T`ed. ~ ~ `
Irsrr~G~.G ~ v"°
f
.
..F
•
.19 Odd wind. !~+'sha es such a ons trr " es and diamonds are enerall ina ro riate.
Shutter's a . orm Windo
.20 Use shutters only if appropriate to the style of the house. The introduction of exterior
shutters to a historic building when there is no evidence that shutters were a historic feature
of the house, is inappropriate:
.21 .l9 Reintroducing missing shutters is encouraged if evidence of the original shutters
can be documented.
.22 .20 While shutters need not be operable, then should be sized to maintain the
appearance of operability.
Jlpsda Netns p~*II D
.23 .2~ Improving the energy efficiency of older windows can often be addressed through
simple repairs. Storm windows or interior energy panels are alternatives to window
replacement. Wood storm windows are preferred. Metal storm windows may be
appropriate if the frames match the nronortions and profile of the original windows and if
the frames are anodized or painted so that raw metal is not visible.
l~~ t , ,yf,~,v~~~~ ~~,~-*~~~4~~-~~, ~rn ~~(/t~a-vat ~ ~'~w~e~~c..
G~ ~ f 5~ ~ -~`b2t. c~4 f'F`7`~ ~ .dh ~C#~ OY"'
3.8 Doors and Storm~oor-s
Front doors and primary entrances are among the most impo lu ent f historic buildings.
The original size and proportion of a front door, the details. do door surround, and
the placement of the door all contribute to the character o e enir
n
Some homeowners may wish to re lace their historic doors" rove ever
Research indicates that in most cases however t)ze ener o an ok "can be
increased to that o a thermal ape re lacement b weather-stri nd the a lication o an
interior or exterior stornz doors stem. However i a roe owne re nest a
landmark alteration cerTi zcate to re lace doors on. "'~94 • utin or i uall landnzarked
buildin the ste s as outlined in the historic Wi "ow an Re la ent/Retro rt
~nlicatiorz Guidelines must be followed. 5
'rv4}pi {t~y.9
a~ L 6
GUIDELINES
~r ry'
.1 b .Whenever Qossible, retain and
reserve a14. 'pal doo or o ' ~ :The location of [he doors ro osed for
retrofit lacement is im tin as sin their si ificance to a historic buildin . In
ener w'` a more im ortant t evasion the less ]ikel that re lacement of a historic door
wi I<` ~ riat~ Elevation 'll be cite orized as rima secondar or terti using
the meth ' set out in th indovv & Door Re lacement A lication and Surve .
• Re laceme ~ tac toric doors on rimar • elevations is rarel a ro riate.
• Re lacement` historic doors on secondar elevations is enerall ina ro riate.
• Re lacemenCOf act historic doors on tertiar elevation can occur rovided it does not
compromise the historic integrity of the building.
.2
- e r b ,
flanking-ivitrdews:-The historic sienificance of the door(s) proposed for replacement must
also be assessed. In general. the more significant a door is to the house as a whole, the less
likely that a retrofit or replacement will be appropriate. The appropriateness of a door
renlacernent will be determined, in part, based upon characterization of the door as either
`Very Historically I~ortant', `Historically Im~rtanY, or `Non-Historic'. (See
Definitions).
A~endeMem~
C I) ~
11.3 TT~_ ^ i..,.l....~ ,l v ~ a f «,ro.. th,.. ,.x ...,~xx~fica=,taxd
vrnro,nv zo
zogo ai°c ¢vcr xc¢oo.z co ac u
should-be-~r~:~~The condition of the door(s) shall be evaluated prior to determining
whether the door(s) should be repaired or replaced. The condition is to be determined by
assessing its elements individually. The assessment will be completed through the use of a
survey that is intended to identify the extent of deterioration in each window and to
determine whether the windows should be repaired, retrofitted, or replaced. The survey
fo,m documents the existing condition for the window and identifies which features will be
repaired and which will possibly be replaced
_4 .b.
o,.^^.,
~~^a -~°~^-'°-Retain and reserve the c ' pal ottional and
---==-r---- -
decorative features of a rim entrance. These featu u oor and its frame
sill head ~arnb moldin s and an flankin window -
5 >
.
~~-~•Historic hardware hip es locksets and knobs feat res that are
significant and should be preserved. ;'T
.6
air ama 'pal doors and door
assemblies whenever ossible folio reco ri d re rvation methods.
.7 ,
rou a Window & Door A lication Surve
re I t is found to be a riate the re lacement door should match the on ~nal as
clas~el Bible. If docum lion of the on 'pal door is not available then the
a Baran ere laceme oor should be based on on 'pal doors on similar historic
structures. ~ ~w~~;xk,
?'si.
.8 0
Replace wood doors with wood doors.
Although good syn~hetic materials are available the use of historic materials is
recommended.
.9 P L, I.J 1. .7 . :tl, ..,.,ce.:..l.......:1 ......1.. ....w:..., f:.." M ^~'-imi~$vior
r~^r
~ - a If energy conservation and heat loss are a concern, consider
usinr a storm door instead of replacing a historic entry door Generally wood storm doors
are most appropriate A metal storm door may be appropriate if it is simple in design and if
the frame is anodized or painted so that raw metal is obscured.
Apwda Nuns G napes 1 t Z
(Underline indicates new language, strike indicates deleted language)
8.2 Energy Efficiency
. In 2006, Boulder's Ciht
Council adopted a Clin:nte Action Plan to meet the Kyoto Protocol goals o substantial) ly
ower
ernissions of greenhouse uses. It is the city~s aim to create compatibility between historic
preservation and enerQU e
ficiennr op
als. In the historic districts and on individualhr
landmarked~roperties, it is important to ensure that energ~e~ficiencu concerns are addressed in
ways that do not damage or diminish the historic character of the building, site or district. It is
recommended tluzt be ore an ener a ~cienc a ades are mode an a er audit is conducted
to deternline the building's current energt
l/ oss•
In historic districts, a variety ofenergy-conserving site and ilding
fe strate the
sensibility of an earlier era to climate and energy efficiency. u " Ily to de ees
buffer residences and sidewalks from the summer sun. Proje orches prove outdoor
space and lessen the impact of the harsh sunlight on the build' rior. Opera endows
and shutters allow occupants to control the introduction of s nlig eezes within the
buildings. An understanding of how such historic features enhance e` ;r~~nncy is critical to
maximizing the energy efficiency of historic buildin ~
For more in ormation re ardin the ever nud' o rn " n ~~cienc in historic
buildin s lease contact the O ee o Env'. m 1 airs.
° .
GUIDELINES :y
.ti.~,,::.;:3~u.
us=e ~ r` ' ~
.l Retain and eren -conserving features of historic buildings
and the' es, incliz de tre es, and operable windows, transoms,
shutt . and blinds.
.2 ~ e thermal effici ~ of historic buildings by observing traditional
prac~ ch as weather - ipping and caulking, and by introducing appropriate
energy- t features, B3bch as storm windows and doors. See Guidelines 3.7.18
and 3.8.7 f 'tiona
=lrection.
~e. `x'
.3 Replace deterior~ d or missing wooden blinds and shutters with matching new
units sized to fit~e opening. See Guideline 3.7.16 for additional direction.
.4 It is not appropriate to install solar collectors in locations that compromise
chara ter-definui roofs. The ntistallation of solar collectors located on a
rominentl visible ro a ~ be a ro riate rovided it does not detract from the
~ historic character of the iro ert1~ or historic district.
~ftt~ t~ (G~'V`I `~'Lz ~-v G'~(Gy"r.l :,f~r5 ~,f'F1
Iii If
{ ~`~%~r~Mc` ~ki':!r"~ z l:e,~ z%1 ~`!•k/1 tr'# ~,I ~j~1 ~li,~,/' Gf ~'~"~i w r° lFlft7"~°
} ~ 4-1 N.~~'" ~~7%~}'} 1. ~°°tk C ~1 L G~:.F`U',r .e't G: ?'T~, ~~c°';r..
}
k y
~ C 1 ~ 3
8.3 Mechanical and Utility Facilities
GUIDELINES
.l If a new mechanic8l system is needed, install it so that it causes the least amount of ,
alteration to the building's exterior facades, materials, and site features.
.2 Locate newmechaniralequipmentandutiLilies,inctudm 'tionumgunits,
in the mostinconspicuous area, usually along abuil ' faca themfmmview.
.3 Where possible, locate portable window air-con v 'ts on " aca yes or
inconspicuous side facades. Consider noise impac ighbors w _ _ cling
sites. ~
.4 It is not appropriate to install ventilato ~an ' . ;skylights,
satellite dishes or other mechanical equi ' cati tha~ompromise
character-defining roofs, or on roof slo s that ntIy visible from the
street.
5 M;nim;~e the visual impacts of t~'ash storag ~ ice areas by screening them
from the street. -
r 4 r.
y i
~ e
: gam...,
Glib ~ a~- -F~~ l~w"t`
I',~~sX~tG#~",~ v~vw7.~.~a"WS, 1Nr Vi~tt,~ GS'~4~--z.~~16~
~k~t~ yufi
w-~~~~~
Imo:
~ I I ~
4
(underline indicates new language, strike indicates deleted language.)
9. DEFINITIONS
Alignment The azrangement of objects along a straight line.
Balcony A railed projecting platform found above ground
level on a building.
=ice;'-
Arch A structure built to support the weight a A tme azch is
curved. It consists of wedge-shaped sto s or bri voussoirs (vu-
swai put together to make a curved e w s opening.
Baluster A short, upright column or um-shaped s of a railing.~~'
Balustrade A row of balusters and the railing ,ling the a stair rail
and also above the comice on of a boil
Bargeboard A projecting board, often d~hatn; ''.s~trim to cover the ends of
the structure where a ed ferh gable:
`s'
Bracket A supporting m ~ or a projec went or shelf, sometimes in the
sha v sometimes as a solid piece or a triangulaz
Cantilev~' A projecting be 'der qr~
other structural member supported only at
one end; used to port a balcony, cornice, extended eaves or any other
;a;~gxtension to a b g or structure.
4,+y
_ '
Column A ght structure; generally consisting of a cylindrical shaft,
base, ,and pillaz: It is usually a supporting or ornamental member
in a b ing.
Contributing Buildings
Those buildings built during the district's period of significance that exist
in compazatively original condition, or that have been appropriately
restored, and cleazly contribute to the historic significance of the district.
~ Such buildings may have compatible additions.
Contributing-Restorable Buildings
Those buildings built during the district's period of significance that have
original material that has been coveted, or buildings that have
AQBIIdB iblll/ V l~#~?
experienced some alteration, but that still convey some sense of history.
These buildings would more strongly contribute, however, if they were
restored. Such buildings may have less compatible additions.
Cornice A projection at the top of a wall or the rop course or molding of a wall
when it serves as a crowning member.
Deck An uncovered platform, usually with wood decking and railings, that
extends from out from the main face of a building.
Dormer A window set upright in a sloping roof. to refer to
the roofed projection in which this win is set.
~r r
`~t_.
Eave The underside of a sloping root projec ' the waf.a b~ildmg.
~~:1?+
Elevation A mechanically accurate, "head-on" dra 'erg ce of a building or
object, without any allowance for the effect df s of perspective.
Any measurement on an elevati a fixed pro ` or scale, ro the
corresponding measurement e ' din.
Facade The front or principal f of o ide of a building that
faces a street or other space. = , '
~
Gable Buildin ends a level of a pitched or gambrel roof. In the case of
a ~ ~ tak rm of an angle. The term is also used
,
ssietime .,to the nd wall.
'1'~S"s.~
C:_
Historl„~~gntext
An organizing suture for interpreting history that groups information
`~yout historic prerties that shaze a common theme, common
aphical a, and a common time period. The development of
cont.. " is a foundation for decisions about the planning,
id ,evaluation, registration, and treatment of hisroric
prope , ,based upon compazative hisroric significance.
Historically Important Window or Door.
The feature has retained integrity from the period of sifnificance and is
an integral part of the historic design or is essential to the understanding
of the architectural tyke or stvle.
Historic Integrity
The degree to which a building has retained its original elements.
Human Scale
Human scale refus ro the relationship between the dimensions of a
Agatdo Netns
C~ape#
building, street streetscape or outdoor space ro the average dimensions
of a human body.
Individually Significant Buildings
Those buildings that aze considered individually eligible for the National
Register of Hisroric Places or for local landmazk designation. These
buildings have a special character and historical, azclutectural, or
aesthetic interest or value in Boulder's local history.
Interior Energy Panel
Interior energy panels are single pane gl ro the interior
of historic windows in order ro reduce c ve oss and prevent
the infiltration of cold air from outdoor ~ They az 'on for
increasing energy efficiency without repl t.
.xt
~.r~ N?~h.
Landmarks Board
The City of Boulder's Landmarks Boazd mns' ve volunteer city
residents appointed by the City C B to consi " ations and
make recommendations ro Co k toric district
designations and to review p pos ' t rayons to Landmarks or
within landmazk districts. ~ ~
Landmarks Board Design Revie mmittee
A Committee tha is of two ~ s of the Landmazks Boazd and
one of t1t'e g Department staff and meets weekly ro
r ~ cer ' p~ations.
Mo IdmQ A decorative b r~_r strip dfmaterial with a constant profile or section
designed to cast resting shadows. Generally used in cornices and trim
around window door openings.
z ;
Mullion verticiember sepazating two casements; the vertical baz
be E 'led windows or multiple windows; the central vertical
mem ~ ~ a double-door opening.
Muntin One of the thin strips of wood used for holding panes of glass within a
window; also caB munnion, baz, sash baz, munton baz. Also, the central
vertical member of a door.
Non-Contributing Buildings:
Those buildings built during the district's period of significance that have
been altered to such an extent that original historic elements aze not
interpretable, and restoration is not possible, also buildings erected
outside the period of signficance that aze not individually significant.
~~r ~ P„o.# I!~
i
Non-Historic Window or Door.
Windows or doors that have been replaced or aze so extensively altered
that they aze inconsistent with the pattern proportion or marerialih~ of
the historic window or door.
Non-Hisroric windows and doors may be retrofitted or replaced.
However the character of the retrofit or replacement should be
compatible with the hisroric character of the building. (See Section 3.7.151.
Parapet A low wall or protective railing; often used a ba~ony or balconet,
' or along the edge of a roof.
z
Period of Significance ~x
The time period during which the major ontribu ' j ` sin a
historic district were constructed. Thep 'gnificanc'~ ally
established by the designating ordinance for "ct.
Pitch The slope of a building elemen exp ratio of
verflcal rise per horizontal ru~F e.g,. i cafes a rise of 3" for
every 12" of horizontal run. p n~'
a_~.
Plate Height The distance betwea,rt ' founds topmost horizontal piece of
framing at the to ~ all and w_ ' ~ next floor framing begins or
where„~hg.z[pf f
Post Auprece of w~` 4 etal, ekc~~ually long and square or cylindrical, set
i upnght to sup buildutg sign, gate, etc.; pillaz; pole.
Prima 1?~' t~'
' opt or '"~i al face of a buildin or an side of a btuldin that
Pa` ' ~ - ub ' r ht of wa or other im rtant ublic s ace such as a ark
T i~~ 'e Ea ode of a buildin is the ost rommen levation and _
wilt co~;l°ain character defming_doors and/or win ows. ~~~~yit~ ~
Protection The actor process of applying measures designed ro affect the physical
condition of a property be defending or guazding it from deterioration,
loss or attack or to cover or shield the property from danger of injury. In,
the case of buildings and structures, such treatment is generally of a
temporary nature and anticipates future historic preservation treatment;
in the case of azchaeological sites, the protective measure maybe
temporary or permanent.
Retrofit In a rehabilitation project the installation of new materials into an -
AgetraNem* C Paps# 11$
existing_fabric. For example, a retrofitted window would be the
installation of new glass (i.e. low a glass) that is fitted into an existing
window sash.
Roof The top covering of a building. Some types:
Gable roof has a pitched roof with ridge and vertical ends.
Gambrel roof is a vaziation of a gable roof, each-side of which has a
shallower slope above a steeper one.
Hiy roof has sloped ends instead of vertical ends.
Shed roof (lean-ro) has one slope only and is built against a higher wall.
Jerkin-head (clipped gable or hipped gable),; ro ~pble but with the
end clipped. - `
r
Sash A window component. see window p rt
Secondary Elevation: _ - '~'»r -
T icall a side of a buildin that has 1 ri ' ibili and ma have
fewer si ' icant character defuun features a ode.
S(ding The narrow horizontal or verkal w ds;hat~f m the outer face of
the walls in a traditional wo a~b+ o ontal wood siding is
also referred to as claplattKds`.' a "s' is also more loosely used
to describe any matgri~at can to the outside of a building as
a finish s~~~i
~ ~
Sill ntal " iqa frame or opening for a window, door,
h~~3T flamed ' ~ - azhho ~ ~ `
' .
Simulated ~ ,Light Wit~'ow
s th ave muntins affixed to the inside and outside of the panes
of gliQ~late the look of a true divided light window.
:n u '
-,t ~ c ~r.Nt~t~~- ~ k~ QS Ct-c~4~'H l~ rr~
Soffit The underside of astwcauaLpart, esefa-beeer, azch, etc. ~
Tertiary Elevation:
The side of a building that typically has little or no visibility from. G~
public street ~ - ,tA[sr.~ ~.(j(~,.~ ,g~ Rl'l~i'~/
r t~1.F ~i+^ }~,csir'.~. F °v~""~7 ~1j~~. ~
°.~G'Y Vt ~'f 6.~-
True Divided Light Window J 1 ;J~~~~~
Windows that use muntins ro form multiple individual panes of glass in
the sash. ~-P.Y~I ~
~ ~ lid
-i-~t~`~~ ~G1r"
aeende Gems C p~,~ 119
Vernacular Buildings in indigenous styles constructed from locally available
materials following traditional building practice and patterns and not
architect-designed.
Very I-Iistorically Important Window or Door
A window or door that has retained substantial integrity from the period
of significance and is characterized by at least one of the following_
1 Defines the azchitectural type or style of the building and without
it the architectural sign~cance would be lost.
2. Is constructed of a rare or unusual material that would be difficult
or c stl tore licate i.e. stained or a da lass
3. Was executed with a hi Ig
t de~ee.{ > ~p that would
render its restoration difEctdt o ~ostl .
4. Conve s artistic merit throw h ul i ~ ra deli
material and color which is of ei 1r
visual u '
5. Demonstrates su erior craftsmans is an exam ~t!e
mlcontmon throu¢h elements of : fi Fal desi details or
craftsmanshi flat aze re rese tative of 'fic t innovation
Visual Continuity
A sense of unity or belongin ~ e by elements of the built
environment because o on
Window Condition: - ~
Class I: Small re airs whi'` - isnally erformed as art of a buildin 's annual
m ' am. a include aint removal re- lazin
' a er=s caw re aintin
r,
iPh' .
Class Iks~ Shows a small d' ' e of Fi sica] deterioration but can be r aired in
placeb~atchin~` aterproofing consolidating or re-eluinQexisting
' tenal•
:*;y?:~ a~~~
A °i~
Class III: d '~ioration in s ecific areas that can be removed and
re out re turin a full feahue re lacement.
Class IV: Damage beyond repair, htcluding a completely rotted window sill,
cvazpin~ or a combination of Class III repairs.
Window and Door Replacement Application and Survey
An application & survey whichmust be submitted as part of a Landmark
Alteration Certificate for the replacement or retrofit of a window or door on a
historically designated building The application and survey outline the methodology
used ro identify the condition: location and historic significance of the window or door
and is used ro determine if replacement, retrofit or repair is appropriate.
Apstde Ilem~
"Gape/
Window Parts
The moving units of a window aze lmown as Sashes and move within the
fixed Frame. The Sash may consist of one large Pane of glass or may be
subdivided into smaller panes by thin members called Muntins or Glazing
Bars. Sometimes innineteenth-century houses windows were arranged
side-by-side and divided by heavy vertical wood members called
Mulliarts.
Head Jamb •q•, ~_a`,
RaU Wit.^t~r~.
°
i$?a
Interior
(:asirg a
c~
Upper Sash a~a ,
Paning Stop ~ •
files
Check Rail
:i
Lower Sash
~ Blintl Stop
' i Interior Srop
Stool uMins
i
Apron t
Skle Jamb
Sill ~ / I - ',y ~r
UV
vti!rt~ c ~i,~rf .~-r-v ~~vt.+~~=~"vtr~
c ~ v v?
~ 6r~~
~ G ~t:12)
Historic Window and Door
Replacement /Retrofit Application
The Landmark Alteration Certificate request process to replace or retrofit
window(s) and/or door(s) on contributing buildings in designated historic
districts or individually landmarked buildings is as follows:
• Submit a completed application to historic preservation planning staff
identifying the location, significance, and condition of each feature that is
proposed to be replaced or retrofitted.
• The proposed replacement or retrofit pro ct ~ entifted and deemed
appropriate as an alteration to a histo ildin
• Staff will review the application and ermi e i th ement o..retrofit
is appropriate.
• If
further deliberation is required, the 'll be reviewe esign
Review Committee and/or the full La` enervation Advisory Board.
Submission Requirements: n`- " " tr~=,
• Completed Landmark Alt to Appli n
• Completed survey sheet '`i tifyi 'on and type of the window(s)
yF
or door(s). ~ ~ z' ,
x3^
• Context photogr `zff the bu g to i ~ ate the historic character of the
windows in r to the ove
• Detailed phot " showing t ition of the window(s) and/or door(s)
• orm' ing the proposed replacement or retroftt product.
a c e ei submitting section drawings of both the existing
and propo dow /or door(s) or by submitting by a list of
~ measuremen parin he individual elements of the existing window(s)
nd/or doors he proposed one(s).`
' LOCATION
,
The location of a that is proposed to be altered is an important
consideration wli termining whether or not replacement or retrofit is
appropriate and needs to be determined as part of the application process.
Typically, there is a hierarchy of elevations on a house. The facade, (primary
elevation) of the house is usually the most important and in most cases will have
the most ornamentation. The sides of-the house (secondary elevations), while
usually less visible, still may contain features important to the character of the
building. The rear elevation can be altered without compromising the historic
character of the house. In general, the more important the elevation, the less
Windows and doors that have suffered catastrophic damage through events such as fire may be assessed
as to condition without first determining location or significance.
~.a.~~ G Papsi~Z2
likely that replacement of a historic window or door will be appzopriate. The
appropriateness of window and/or door replacement will be determined based
upon characterization by staff and the landmarks design review committee using
the following location criteria:
Primary Elevation:
Includes the facade (front or main elevation), or any side of a building that faces
a public right of way or other open space. In general, the facade of a building is
the most prominent elevation and will contain character defining doors and/or
windows. Replacement of intact historic windows on primary elevations is
inappropriate.
Secondary Elevation; ~ ~~v
Typically the sides of a building have less pu visibili ~ y have ewer
significant character defining features than Replac ~ of ' t
historic windows on secondary elevations is ra propriate.
' .
Tertiary Elevation:
Tertiary elevations typically have little 'sibility e public right-of-
way and are usually located at the r ~ 'ding. ~ they may have
character defining windows or do 'm retrofit or replacement of
windows or doors on a tertiar ~ele~v~tio oc -out compromising the
historic integrity of the boil
}
.w ~°k, SIGNIFICANCE'
Next, the ~ ` 'cane a door(s) and/or window(s) proposed for
repla* Ott must b sed. eral, the more significant a window or door
is t R .,ouse as a wh a less' ely it will be that retrofit or replacement
will tits: ,,,opriate. The ropriateness of window and/or door replacement
wtll be d' ned base on characterization by staff using the following
si tEicance is z`
Very Historical rtant:
The feature has ref ed substantial integrity from the period of significance and
is characterized by at least one of the following:
1. Defines the architectural type or style of the building and without it the
architectural significance would be lost
2. Is constructed of a rare or unusual material that would be difficult to
replicate. (i.e. stained or leaded glass)
3. Was executed with a high degree of craftsmanship that would render its
restoration difficult
t Windows and doors that have suffered catastrophic damage through events such as fire may be assessed
as to condition without first determining location or significance.
~ Cam,: r23
4. Conveys aztistic merit though skillful integration of design, material, and
color which is of excellent visual quality
5. Demonstrates superior craftsmanship or is an example of the uncommon
through elements of architectural design, details, or craftsmanship that are
representative of a significant innovation
Historically Important:
• A historically important feature is one that has retained integrity from the period
of significance and is an integral part of the historic design or is essential to the
understanding of the architectural type or style.
The feature has retained some integrity from th eri ficance for the
building and maybe ordinary in execution s 1' ~ ' ue in
understanding historic type or style.
Non-Historic: _
A non-historic feature is one that has been re has been so altered that it
is inconsistent with the pattern, proportion or mate " ~ .;of the historic window
or door. Non-historic windows and d be retr ' J' or replaced. ,
However, the character of the retro ' ~ ent sho a compatible with
the historic character of the build' ee s 13).
•n:. ~a-..
Once the location and the si _ ~ ance o e feat ~ ave been determined, the
significance/location ma i used to ~ `the proposed replacement or
retrofit of a window or ay be app ` :Note that acase-by-case review
is handled ~ ly b and maybe evaluated by the DRC and/or the
Land A Board. If a property owner wishes to request
a La Alterari tific windows and/or doors that are Very
His - ly Important a loca , °on the primary elevation, the case will be
revie the Design 'ew Committee and maybe reviewed" by the
Landma servatioy{ visory Board.
~~[i"t4 . Y kti~
GYt
~,,ss
- AoNaa Nemte C P~pe# 12y
Historic Window and Door Significance/Location Matrix
Very Historically Non-Historic
Historically Important
Important
Primary Elevation
.
+ I~~Y are-
:Ati ' ~ i
~~N:
Secondary cS se~b}
Elevation ' case
~ r .
`~i:.
k,r .
Tertiary m=~
Elevation
CON. ~.~ON
t--~
If it has been determined that it is a ~ ~iate~fQr possible'.etrofit or
replacement per significance and 1 `'on ~v~luation, or that staff and the
Landmarks Preservation Advi,~ry ~oarpl~ esign lZevzew Committee considers
that catastrophic damage may'~~varrant ~x~dition evaluation without location_or
r~ ~
significance consideration, tl~e conditio ~h~r;ldow or doors must be
evaluated. This is done by assessing ele~'e~~idividually.
The condihori~th~f'tle'window must be evaluated by examining the individual
elements through the attached srtrv~y.
In order to;~complete a window survey the following information is needed:
: Cl..ear, colored;:-detailed photographs, including at least one of each:
1. Full-frame shot of the entire house
2: Full-frame shot of individual windows from the exterior
3': Full-frame shot of individual windows from the interior
4. `Close-up views of intersection of sills and frames
5. Close-up views of sash, focusing on bottom rail and muntins
(if existing)
6. Close-up view of sills and bottom rails from the interior
• Completed survey form
The survey form documents the existing condition for the windows/doors and
identifies which features will be repaired and which will possibly be replaced. It
should also indicate the window,location and corresponding photograph. A
window on the north elevation would be WN1; a door on the south elevation
C- ~ 125
i~W
would be DS1. The existing type denotes the material and the type of
window/door that it is. For example, WD DH would be wooden, double hung
and MTL CASE would indicate that the window would be a metal casement. The
type should include the number of lights in the sash. Possible examples could
include twelve over twelve (12/12), six over six (6/6), or one over one (1/1).
There is also space for additional remarks when necessary.
A four level classification system is used to document the existing condition of
each of the windows or doors. This classification is based upon the system
identified in the National Park Service publication, Preservation Brief #9, "The
Repair of Historic Wooden Windows". The appropriateness of:;window and/or
door replacement will be determined based upo~.characterizafon by staff using
the following condition classification criteria f
r'
~~y~ -
Class I:
"Routine Maintenance", associated with small repairs, which are usually
performed as part of a building's annual mairi~tenartce~rogram. May include
paint removal, re-glazing, weather-stripping, caulking, aid repainting
rq a
Class II: ~ ~ y -
"Stabilization", shows a small degree of phy~'aI`deterioration but can be
repaired in place by patching,,vvaterproq,g, coiisoliclating, and re-gluing
existing material.
,f~-
Class III: 1 J. __`~''~g',
~h{
"Partial Replacement", localized deterioration in specific areas that can be
removed ~nd`replaced withoutrequiring a full feature replacement.
Class IV:
"Total Replacement" is fir windows that have been damaged beyond repair.
This includes~a completely rotted sill, warping or a combination of Class III
repairs.
On the survey form: under 'Existing Conditions," the sash, frame, sill, glass,
muntins and casing are rated as to whether it is Class I, II, III, or IV. After all the
windows have been rated, they are totaled by class for each of the window
elements: sill, frame and sash, glass, muntins and casing are compared. Those
windows in Class I, II and III should be repaired and those in Class IV should be
replaced in kind (See section 3.7.13}.
PROPOSED RETROFIT OR REPLACEMENT PRODUCT
Applicants are encouraged to repair the existing windows or doors rather than
replace them. If the existing condition of the window or door, as documented by
a window survey, indicates Class III or N damage or deterioration, then the
c ~
-'bus h~, ~ 1h Lt: ~ ~ vti
z,~: ~...~.~'?t~~
av~€,..i~,i~y ~ tn~~ a,~re. ~ ~ r~~rd~~
GUfy"t`~"Y7'} bl+~~ lfi} ~a ~ ~ o-
r r
windows may be retrofitted or replaced All retrofitted or replacement windows I Eu~r~C.
and doors must match the historic as closely as possible. t~,~I~
\The selection of replacement windows should ~t begin chat-s
•..n. ~,••+...,+Ho,. with what is being replaced. A major concern w/ (~LL;~~"V1~
with replacement windows or doors is that they often do not accurately replicate /~L~~~IIr?6"
the historic appearance. Replacement sash should match historic sash in pane (t!y 4 t~,
size and configuration, glazing, muntln detailing, profile and historic color and Crt' ~
trim. Frequently, the profiles of replacement elements, such as muntins, sash,
frames, and moldings, are flatter and wider or narrower and thinner than the
historic profiles. A-~ui~y duplicate the ex nu r of original
panes, but a change in relief affects the character f th' windows, which
in turn alters the overall appearance of the en ' uildi refore, a window
comparison is required for all proposed repl ~ ends. s done ether
graphically or by measuring individual elem ~ Gf~'~a ~
The first approach is to submit a set of drawi ring the profiles of the
historic window or doors to the proposed replacem r a section submittal,
the following information is required °:r~ ~~~,y
3. v ~L4r~4
• Full horizontal and ve ' 1 se a existing windows or doors
• Full horizontal a"1'ertical ' tions he proposed replacement
windows or fit? (3"=1'0).' mdows or doors do not exist
...rc
and no evi • ~f the piston ` arance can be found, then only
seep e required.
N.
Wm "end door se ~T` mus`~refully detailed so that all parts are shown
and ials are sped ~ "'tA section must show the profiles of muntins,
meeti ~ ,sash, fram d moldings. It should also show the window or
door's re hip to th sting wall. Attached is an example of vertical
window se~~pf botl~,r istoric_ and.a replacem~nk xytndow. The new
min-low's pro °~`Tesembles that of the existing window - ~;'x~'((~y~'"~_ ' ~
A second option is to measure each window element individually, and compare G~~'+~"~ ~=~'v~'t6"
the existing dimensions to the dimensions of the proposed window or door.
Measurements must include size, muntins, meeting rails; sash, frames, and
moldings. ,
A9w~Nemf ~ Pope# /
2 ~ ~
- Window and Door Survey .2x ~G'~~,~ ~ g
%~g, posed Type v
Location Existing Type Existin Condition e',~. ~ Comments 'K
Re air Class ~ ,
sash frame sill lass muntms
' F~ ~r]~ii.
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9
BUILDING TECHNOLOGIES
Response to the draft revisions to the "General Design Guidelines for Boulder's Historic
Districts and Individual Landmarks."
Larry Kinney
LarryK@ SynergisticBT.com
October, 2007
Overview
I believe that the preservation of historically designated buildings in Boulder is a high calling
that should be done well. I have been involved professionally in retrofit work on existing homes
for 32 years, from the evaluation and supplying of training and technical assistance to public
weatherization programs to the developing of techniques and devices aimed as saving energy
cost effectively. This includes extensive reseazch and development in the field of fenestration,
examples of which are available at the web site on this letterhead. I am the principal author of a
brochure and pair of volumes on the subject of "Making your Historic Building Energy
Efficient" whose primary target audience is citizens who live in historically designated buildings
in the city. This work was co-sponsored by the city of Boulder's Historic Preservation Program
and the Office of Environmental Affairs, members of whose staffs commented extensively on
drafts of the documents.
Most historic buildings in Boulder are presently very energy wasteful. Retrofitting them to
lower this waste extends their lives, increases comfort, and lowers energy costs precipitously.
With care and attention to detail, they can be made much more energy efficient while preserving
historic authenticity and integrity. I believe that a great deal of this work can (and should) be
accomplished with minimal effects on the outside appeazance of a historic structure, save to
enhance it in ways that make it appear more historic authentic than is presently the case.
Windows
This observation includes work on windows.
I agree with the new language in the draft Guidelines, to wit, "the introduction of weather
stripping, insulation, or materials to improve the operation of historic windows must not be
visible form the exterior of the building" In most cases, i[ is possible to lower the convective
losses (leakiness) of windows generally and conductive losses associated with weight pockets
without a change in appeazance on the outside or the inside of existing windows, given that they
aze in a condition to be repaired at all.
However, insisting that single glazing be retained is a mistake, guarantees energy waste and
discomfort, and ignores recent substantial advances in the technology of windows and glazing
systems. Here are some realities:
Synergistic Building Technologies, Inc. 1335 Deer Trail Road Boulder, Colorado 80302 USA
303.449.7941 (V) 303.546.0343 (F) www.SynergisticBT ~~S ~ 29
Glazing Analysis for Historic Homes Page 2 January 30, 2006
• On a night when the inside air temperature is 70F and the outside is OF, the center of
glass temperature of a single glazed window is 17F, that of a double glazed window 45F,
that of a double glazed low E with argon filling is 56F. These numbers express both the
relative magnitude of discomfort due to radiant energy losses and overall energy losses
heating system has to make up.
• The heat transfer across a double glazed window system (either an insulated glass unit or
a storm window) varies with distance between glazings and the gas that is between them,
air, aggon, or krypton. Too close together and conductive losses predominate; too faz
apart and convective losses predorrvnate. For air and aggon, the sweet part of the curves
occurs around half an inch; for krypton, the spacing between glazings to achieve minimal
heat transfer is a quarter of an inch. Conventional single glazed windows have a heat
transfer coefficient (U factor = 1/R value) of about 1.3 Btu/ftZ/°F. A double glazed
window with a low emissivity surface and krypton fill with'/a inch between panes has a
U factor of 0.23 Btu/ft2/°F, 5.7 times lower.
• Low e hard coat surfaces cannot be observed with the eye. Yet they contribute
substantially to comfort and energy savings in the winter. They should be encouraged,
not disallowed.
• It is possible to form an insulating glass unit using an existing ancient, wavy lite (pane)
with a second life whose inside surface has aloes-e coating on it. Picking a spacing of/a
inch between lites and filling the resulting insulating glass unit with krypton will result in
ahigh-quality fenestration system whose aesthetics from the street are indistinguishable
from the original single glazed system, yet whose thermal and comfort performance are
enhanced very substantially. Again, such retrofits should be encouraged, not disallowed.
• A number of manufacturers of high quality windows aze engaged in the design and
production of windows which will last for on the order of centuries with little or no
maintenance, and which closely resemble wood-frame windows of a variety of styles,
including double hung windows chazacteristic of many historical-designated homes.
When existing old windows have come to the end of their lives, installing such windows
with modern glazing simply makes good sense-and will save many dollars over the
lifetime of the buildings.
Quantifying the Differences
The numbers cited above are derived from Chapter 31 on Fenestration from the 2005 ASHRAE
Handbook of Fundamentals. Of course, it would be desirable to do some actual laboratory and
field testing of a variety of fenestration systems in Boulder. A project sponsored by the State
Historical Fund to do exactly that is underway, with preliminary results due by the late Spring of
2008. In the meanwhile it is useful to make use of modem computing techniques to illustrate
differences in the performance of different window systems.
Definitions of technical parameters and other relevant background information are included in a
report prepared for the Department of Energy's Building America Program entitled "Windows
Synergistic Building Technologies, Inc. 1335 Deer Trail Road Boulder, Colorado 80302 USA
303.449.7941 (V) 303.546.0343 (F) www.SynergisticBT.com n # 130
q®Blldg MOlll~ l• P~
Glazing Analysis for Historic Homes Page 3 January 30, 2006
and Window Treatments." The report is available for downloading at www.SynergisticBT.com
under Insulating Shutter.
Method
To illustrate something of a practical range of options, I have defined five glazing types, all of
which are assumed to be installed in wooden frames. The information shown below was
produced by using RESFEN (for "Residential Fenestration") software using historical weather
data from Denver. It is a special case of DOE 2 software which is the product of many hundreds
of years of professional labor and is the industry standard. RESFEN runs a detailed hour-by-
hour analysis of the energy flow through windows and sums up heating and cooling energy and
costs by facade (since solar exposure plays a key role). For purposes of this analysis, I assumed
that electricity costs $0.10 per kWh and gas costs $1.10 per therm. These are approximately the
current costs to residential consumers in Xcel's service territory. To express them both in a
common unit, a million British thermal units (MMBtu), electricity costs $29.30 per MMBtu and
gas $11.00 per MMBtu, where a MMBtu is approximately the energy equivalent of a person year
of labor.
To compute net costs of energy associated with the windows, I assumed a gas furnace whose
system efficiency is 70% and whose air conditioning system has a seasonal energy efficiency
rating of 8.0, numbers that are likely to be good approximations for older homes and associated
distribution systems in the area.
I assumed windows with wooden frames that are quite tight but have no shading. There are 75
square feet of windows on each of four facades of a home, which would amount to about 15%
glazing area on the walls of a 2,000 square foot home. I then looked at cases shown in Table 1.
Table 1. Five cases examined defined
Case Descri lion U factor Solar Heat Gain Coefficient
1 Sin le-glazed clear 0.93 0.78
2 Double-glazed clear 0.55 0.59
3 Double- lazed Low E 0.36 0.53
4 Double-glazed Low EE 0.34 0.34
5 Tri le glazed Su er Alpin 0.12 0.29
Results
Annual costs arc illustrated in Figure 1.
Synergistic Building Technologies, Inc. 1335 Deer Trail Road Boulder, Colorado 80302 USA
303.449.7941 (V) 303.546.0343 (F) www.SynergisticBT.com~ ~ ~
Glazing Analysis for Historic Homes Page 4 January 30, 2006
$soo
$250. _
$200 - ~ - _
~Y,v~. f
~Y
~.~t,~.
$150 Cooling . ~
-
~ ~ eati
v 9
~ $100 ~ * ~'~5 - - -
}
~ ,
A
' ~
U y} s +i ~
;i
F
$O f ~
t 2 4
-2Co -
-$100 _ - - - - _ _
-$150
Figure 1. Annual costs for the five glazing types consisting of 300 square feet of windows
evenly distributed on four facades of a residential structure. Case 1 is single glazing; Case
2 is clear double glazing, Case 3 is low E double glazing, Case 4 is low EE double glazing,
and Case 5 is triple glazing very low U. Blue denotes cooling costs, red heating costs, and
green total annual space conditioning costs due to windows alone.
Note that solar gain raises cooling costs and lowers heating costs. Since single glazing has the
highest solar gain, it has the highest cooling costs. However, since it also has the highest U
factor (lowest R value), its wintertime losses are also highest, sQ heating costs are higher than the
other cases.
Table 2 shows details of energy consumption by facade in summer and winter as well as annual
summary information.
Synergistic Building Technologies, Inc. 1335 Deer Trail Road Boulder, Colorado 80302 USA
303.449.7941 (V) 303.546.0343 (F) www.Synergistic6 .co ~ C ~ 132
Kinney Response to Draf[ Historic Guidelines Page 5
Table 2. Results of five window systems in four orientations.
North East South West Totals
Person years
Window Cool Heat Cool Heat Cool Heat Cool Heat Cool Heat of labor Cool Heat Total
S stem kWh MMBtu kWh MMBtu kWh MMBtu kWh MMBtu kWh MMBtu a uivalent $ $ $
1 249 9.19 671 1.15 616 -4.62 589 4.44 1509 10.16 15.3 $151 $112 $263
2 195 5.72 500 -0.75 452 -5.39 437 1.81 1132 1.39 5.3 $113 $15 $128
3 180 3.41 450 -2.45 405 -6.73 393 -0.19 1023 -5.96 -2.5 $102 -$66 $37
4 107 4.04 263 -0.16 233 -3.02 234 1.41 604 5.77 7.8 $60 $63 $124
5 97 0.76 226 -2.77 198 -5.29 202 -1.52 723 -8.82 -6.4 $72 -$97 -$25
To reiterate, these numbers reflect energy use associated with 75 square feet of glazing on each facade. Accordingly, one can derive
good estimates for a residence whose window areas (including frames) are different from 75 squaze feet by simply multiplying the
numbers in the boxes corresponding to the appropriate facade by the actual squaze feet divided by 75.
In general, comfort on cold winter nights is an inverse function of U factors and comfort on hot summer days is an inverse function of
SHGCs. Accordingly, single glazing is decidedly worse case in considering comfort, as well as energy use and associated cost.
A similar analysis of winter only considerations using 100 square feet of glazing per facade appeared in the Spring Edition of the
Boulder Green Building Guild. It also considers the interesting case of adding outside insulating shutters, closing them on cold nights.
The article is also downloadable at www.SynergisticBT.com under Insulating Shutter..
Returning to the above analysis, note that the difference between worse case (single glazing) and best case annual energy use due to
300 square feet of glazing is the energy equivalent of almost 20 person years of labor. I submit that this is highly non-trivial and
should be taken account of much more fully in the General Design Guidelines.
Respectfully submitted, ,
h Larry Kinney
IW Synergistic Building Technologies, Inc. 1335 Deer Trail Road Boulder, Colorado 80302 USA
~ 303.449.7941 (V) 303.546.0343 (F) www.SynergisticBT.com
Eric Doub, Ecofutures Building, Inc.
Comments received October 26, 2007
Hello James,
My comments here are regarding the General Design Guidelines draft revisions regarding
windows and doors. Thank you for inviting my participation in the discussion.
Overall I think it is progress that a method is being proposed for evaluating window and
door replacements and retrofits. This is the kind of system your predecessor and I were
just starting to explore, in ]ate 2004.
My Approach
First, I would like you to know I approach the topics in the GDG draft, influenced over
the past year by conferences, trainings, and other study. The 100-person summit in July
in San Francisco was perhaps the most powerful: "Moving Existing Housing
Toward Carbon Neutrality." The stated purpose of the meting was to explore all the
opportunities and barriers, in both policy and technology, to reducing energy use in
existing homes in the US and Canada by 80 to 90% by the year 2020. Excluded from
discussion were onsite renewables: We were not allowed to talk about solar collectors as
part of our strategy to implement these "deep retrofits." We were charged with figuring
out how to get there by using the best of building science to insulate, air seal, and
reconfigure mechanical systems.
What a challenge, with tremendous Teaming for all. We considered retrofits where the
budget was $10,000, and others with unlimited budgets; homes from the 1970s and
1910s; and more.
It is from this perspective that I read the discussion on windows and doors in the draft
guidelines. I end up asking: How can we keep these historic homes from being doomed
by post-peak-natural gas rising energy prices and carbon management plans (from state
and local government so faz, but with a change in federal leadership, possibly from
Washington too)? At what point will even relatively wealthy owners of homes in historic
districts say, "My energy costs are now exceeding my mortgage costs per month, and this
just isn't working"?
I would like to see historic homes receive deep retrofits that make them viable
(affordable, practical) in coming decades.
Bringing existing windows somewhere close to the performance of a "thermal pane"
window (undefined, and nowhere near insulating and air sealing enough to be part of
retrofitting a home to be affordable and worth preserving 50 or even 20 years from now)
is not going to suffice, in light of our community's goal (alluded to in the Climate Action
Plan) of moving existing housing toward carbon neutrality.
One of the nation's top building scientists, Joe Istiburek of Building Science Corp, says
something in his training sessions that provides a framework for how I analyze potential
retrofit measures for homes, whether these homes are in or out of historic districts.
~ ~+'3
' Eric Doub, Ecofutures Building, Inc.
Comments received October 26, 2007
"[Because of climate change and energy security] In the next decade or two, we will have
to build everything with enclosures having two to three times the thermal resistance of
what we have built in the past, and everything we have built in the past will have to be
retrofitted to have enclosures performing two to three times better than now."
Are these Guidelines really in step with where we are going to have to go as a society?
Or are we digging in our heels and Enforcing Obsolescence?
Specific Comments on the GDG Draft
Second, I would like to offer some notes on the draft specifically, to correct several
false premises.
I. In the intro to 3.7, only energy efficiency is mentioned as a benefit of retrofitting or
replacing windows. Here is a longer list:
Energy savings
Improved comfort
Less condensation /ice /mold
Increased light and view
Solaz heat control
Reduced fading
HVAC size decreases
Improved safety: tempered glazing, lack of lead paint dust from old sashes moving
against each other
Convenience of operation /ventilation: Windows that aze easy to open and close
By narrowing the discussion in 3.7 and through the Guidelines to energy efficiency, the
draft is leaving out other important benefits of windows. People want to replace their
windows for some or all of the above reasons, and if the Guidelines and staff and
volunteers continue to systematically not acknowledge other motivations, then
the Landmarks process will continue to be unnecessarily troubled.
As you can see from the above list, retrofitting cannot provide all of the benefits of
replacement.
~ P•oe* X35
Eric Doub, Ecofutures Building, Inc.
Comments received October 26, 2007
In addition, saying that windows are not all that important (the clear message of the
proposed language) begs [he question of "IN WHAT CONTEXT?" One of the
consultants brought into this discussion in 2005 and 2006, Larry Kinney, tried to point
out to participants that windows vary widely in their share of the heat loss pie. There is
no fixed order of retrofit measures that is optimal for each building, and ye[ the intro to
3.7 tries to nudge the reader in that direction: Windows last.
Note: When walls and ceilings are insulated well, and decent air sealing has been
achieved, the windows alone can account for 20 to 30% of the home's total heat loss.
Doors are then another similar slice of the pie, 20 to 30%.
Tt is only when the walls and ceiling aze poorly insulated or not at all, and the home is
extremely leaky, that windows are a smaller percentage of the total heat loss.
2. In 3.7.5, the false premise /wrong question is again offered: "Reseazch indicates that,
in most cases, the energy efficiency of an old window can be increased to that of a
thermal pane replacement by weather-stripping, insulation of weight pockets, and the
application of an interior or exterior storm system."
The Environmental Advisory Board and LPAB got the basic building science of this
wrong in 2005 and 2006. I am familiaz with the "reseazch" that was used in these
discussions it was an article from Home Energy magazine that discussed reductions if
Equivalent Leakage Areas. What was found in that work was that infiltration and
exfiltration could be drastically reduced in old windows, to the point that the retrofitted
windows had approximately the same AIR LEAKAGE as some MEDIOCRE new
windows.
"Thermal pane" means a Center of Glass rating of R-1.9, with no accounting for air
leakage. Good windows nowadays have COG ratings of R-12, with the best being R-20
(made by a local company, too!). Are we as a community ready to agree that bringing an
old window up to the lowest end of the performance scale is adequate? The lowest end
of the scale does not even meet code. So an F- grade is what is being proposed here.
The article did not address, and neither did the EAB or LPAB, how windows affect
thermal comfort: Radiant heat loss due to cold surfaces such as "thermal pane" and
single pane glazing, and cold window frames (non thermally broken frames and sashes),
can make occupants turn up the thermostat to increase the indoor air temperature.
This is what I mean by asking the "wrong question" also evident in retrofitted windows
falling far below performance standards that will meet HERS index requirements of the
new Green Points revision (if this revision does end up including upgrading of existing
living space), and certainly coming nowhere close to being part of the deep retrofits that
will make these old buildings worth preserving.
Eric Doub, Ecofutures Building, Inc.
Comments received October 26, 2007
3. In 3.7.13, it is stated that an applicant should essentially expected to be turned down if
they want to replace single-pane steel windows. I know of one district where this has
been a topic of considerable debate. From a community well-being perspective, the
Guidelines in this aspect are faz off base. In,contrast, historic buildings throughout
Europe, many continuously occupied for hundreds of years, have replacement windows.
The mindset is simply more practical: Let's keep the parts of the old structure that meet
the needs of the occupants and community, and replace the other parts. From a European
perspective, and from my own, and especially in light of the Climate Action Plan, the
declaration in 3.7.13 once again presents the question for Boulder: Leadership or
Laughingstock?
4. In 3.7.23, storm windows are again offered as a legitimate way to treat an existing
window. Several concerns aze neglected by storm windows, whether interior or exterior,
including: Egress and Ventilation. Cost and convenience are other factors.
5. In 3.8, intro, it is again stated that "research shows..." etc. How many full- or half-life
doors are there that might be classified as Very Historically Important or Historically
Important? The language in the intro addresses only this one condition, of doors with
glazing, and a raze condition at that. More common is an existing wood door with an R-
value of less than 1 (wood having an average insulating value of R-1 per inch), with
substantial air leakage. Technically, such existing doors should be compazed to
replacement doors with an insulating power of R-7 (insulated foam core, for example)
with tight, modern weatherstripping and multi-point locking hazdwaze.
6. In 8.2, Energy Efficiency, it is stated that "Operable windows and shutters allow
occupants to control the introduction of sunlight and breezes within the buildings" as an
example of one of the benefits of existing homes. This is at odds with 3.7.23,
recommending storm windows.
(Please note that my training tells me that most of modem construction is missing
fundamental good design in the form of overhangs for proper shading, shade trees, and
porches. I am in no way saying that willy-Hilly modern building, which produces many
homes that are uncomfortable and perform in the 12 mpg range, are any kind of example
to follow.)
8.2.4 Solar collectors: It is still a mystery to me why automobiles aze considered just
fine, to be parked in historic districts, while other aspects of our infrastructure and life
support, such as solaz collectors, are considered a problem from a "historic chazacYer"
standpoint.
What if someone wants to install solar collectors in their driveway, and not own a car at
all? The Landmarks process would probably oppose such a move.
Ott: ~ ~3?
Eric Doub, Ecofutures Building, Inc.
Comments received October 26, 2007
Go ahead and park your Pollution Waste Machine in the driveway or on the scree[,
displaying the kind of machine that kills 55,000 people per year in the US and maims
countless others, and drives our foreign policy toward militarism and war, and causes
global warming, emphysema, asthma in children and adults, obesity, alienation, and
overall social and ecosystems decline and by such display of your car "detract from the
the historic character of the property or historic district" but don't even think of putting
solar collectors on your roof. "Hypocrisy is the greatest luxury. Raise the double
standard." Michael Franti
Policy idea: In any case where the Landmarks process denies window and door
replacements and forces retrofits instead, it could be required to have an energy audit
performed before and after.
Sincerely,
Eric
Direct Line 303-440-7176
Eric L. Doub, President and Founder
Ecofutures Building, Inc.
1025 Rosewood Ave. Suite 204
Boulder, CO 80304-0695
303-415-9694 Main Office
303-415-9332 Fax
303-207-2001 Voicemail Pager
www. ecofuturesbuilding.com
ericdoub@ecofuturesbuilding.com
~.a. ~t~ G P.o,: X38
Lynn Bingham, Phoenix Window Restoration, Inc
Comments received 10/29/2007
Hi James - I finally had some time to read and consider the draft design guidelines over the
weekend. I realize the challenges your group has experienced concerning windows, and I think
these draft design guidelines come closer in facilitating the landmark alteration application
process more effectively. From the perspective of a contractor dealing directly with homeowners,
I've noted two areas that may warrant further consider based on how I've read and understood
the document.
1.) the "recommended" energy audit........I do think an energy audit is a good idea, but it
seems City won't or can't "require" an energy audit for historic buildings. Are there funds
available from the City to encourage owners to do the energy audit when their property
comes under the historic guidelines and energy considerations are a factor? I'm still not sure
some property owners would appreciate this, but it could lessen a perceived, and possibly
arbitrary, denial of an application for lack of an audit that isn't "required". As well, the board
could "recommend" the audit without the homeowner bearing additional costs.
2.) the Window and Door Replacement Application and Survey........I couldn't find this document
in the guidelines. Did I miss something? My main comment is related to the window
survey. Who is to conduct the survey, i.e, the Design Review Committee, a qualified preservation
consultant or architect, the homeowner, or a contractor? There are likely differences how
each might interpret the condition of a window. And, homeowners and contractors may not be
familiar with the Class I, II, II N classification for window conditions or how to interpret
these. The draft design guidelines more clearly defines the important two factors, location and
significance of the windows. But, property owners are always focused on the third factor, the
window condition, as they perceive it. Like the energy audit, property owners will probably be
at odds with the costs for a professional window survey and how to go about getting a survey
done. Maybe a little more explanation and guidance about the survey process would be useful to
the person reading and affected by this document.
Thank you for the opportunity to provide some feedback.
Sincerely,
Lynn Bingham, Owner
Phoenix Window Restoration, Inc. ,
(303) 778-9487, office x3
(303) 870-7709, cell
amens C P,o,# !3~
Page l of 1
James Hewat -General Design Guidelines for Boulder's Historic Districts and Individual
Landmarks
From: "Saldibaz, Joseph"
To:
Date: 11/1/2007 2:48 PM
Subject: General Design Guidelines for Boulder's Historic Districts and Individual Landmazks
James,
1 only have two comments on the new guidelines, both for "Windows in new construction:
Considering between-floor windows and odd-shaped windows, I think it's okay to consider these as possible in
new construction, provided that they are not outlandish. Adiamond-shaped window in a gable end, for example,
is probably not that big of a deal. It also allows a little creative outlet for architects and designers looking to get a
little "punch" out of their designs, without creating something crazy and huge.
Otherwise 1 think the new guidelines took great.
Joe Saldibar
Architectural Services Coordinator
Colorado Historical Society
303-866-3741