6B - Draft Guidelines and application for replacement of doors and windows on landmarked propertiesMEMORANDUM
October 3rd, 2007
TO: Landmarks Preservation Advisory Board
FROM: Susan Richstone, Acting Long Range Planning Manager
Chris Meschuk, Histaric Preservation Planner
Marcy Cameron, Historic Preservation Intern
James Hewat, Historic Preservation Planner
SUBJECT: Review of Administrative Guidelines including amendments to the
General Design Guideline Sections 39 Windows, 3.8 Doors, 8.2
Energy Efficiency, and 9 Definitions and guidelines regarding the
development of significance and condition evaluation criteria for
historic windows and doors.
PURPOSE:
For the Landmarks Board to review and comment on proposed administrative
regulations/revisions to the general design guidelines regarding significance and
condition evaluation for applications requesting the replacement of historic
doors and windows, prior to initiation of rulemaking process. The attached draft
integrates comments made by the Board since the September 5t'', 2007 joint
Landmarks Board/Environmental Advisory Board meeting.
Questions for the Board:
1. Do you consider the proposed amendments to the General Design Guidelines
consistent with the policy direction given by the City Council on January 16'~?
Are the proposed amendments to Sections 3J, 3.8, 8.2, £~ 9 of the Guidelines and
draft Historic Window and Door Replacement /Retrofit Application Guidelines
"clear and objective" per the City Council's policy direction?
3. Do you have questions or comments on any of the approaches and procedures
outlined in the administrative guidelines?
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4. Is there additional information that should be included in the draft guidelines for
establishing significance, condition, and yroposed replacement of windows and
doors?
5. Are there other issues that should be addressed in the guidelines?
The Landmarks Board is being asked to initiate the rulemaking procedure for
adopting administrative regulations Rulemaking, Chapter 1-4, of the Boulder
Revised Code. To this end, staff recommends that the Landmarks Board adopt
the following motion:
The Landmarks Board and Environmental Advisory Board recommend initiation
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 Envirorunental Sustainability
Integration Policy Direction.
BACKGROUND:
The City Council reviewed the findings from the Historic Preservation and
Environmental Sustainability Integration Project (HIPESIP) project on January
16, 2007 (see Attachment B). At that time the Council recommended changes to the
city's policy regarding the replacement of historic windows and doors on
designated buildings to reflect Option B as developed by staff and the Ad-hoc
committee as part of the year-long project. In general, the revised Option B is
similai to the current process Eor determining which windows and dooxs on
historic buildings should be preserved and which may be replaced. However,
this option provides for the development and implementation of clear and
objective administrative regulations for the Landmarks Board and staff to use in
the assessment the relative historic significance and condition of existing
windows on designated or contributing historic buildings.
Specifically, the January 16~'' direction given to staff by the City Council called
for revisions to the Historic Preservation Guidelines and Green Points program
to:
• Require property owners to preserve rather than replace significant
historic windows on designated buildings unless deteriorated beyond
repair (see below).
• Encourage property owners to rehabilitate and weatherize historic
windows by weather-stripping and installing additional glazing.
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• Develop and implement clear and objective administrative regulations for
the Landmarks Board and staff to use in the assessment of the relative
historic significance of existing windows on designated or contributing
historic buildings.
• 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.
• Encourage the installation of storm windows that match the materials,
proportions and profile of the underlying historic window as closely as
possible.
• 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.
• Allow shutters where there is historic precedent.
The revised Option B endorsed by the Landmarks Board, the Environmental
Advisory Board, and the City Council requires case by case review of windows
and doors proposed for replacement on historically designated buildings.
Implementation of regulations to reflect this policy requires the development of
standards to assess the historic importance and relative conditions of historic
windows and doors which will 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 6-10 weeks.)
The General Design Guidelines were originally adopted in July of 2003. Since
then, there have been a significant number of cases requiring a clearer outline for
determining the appropriateness of window replacement on a historic house.
At the joint September 5t'', 2007 joint Landmarks/Environmental Advisory Board
(EAB) joint meeting, the Boards reviewed and commented on draft guidelines for
the replacement of windows and doars. The EAB was generally suppartive of the
approach outlined in the draft guidelines, however, the Landmarks Board felt it
needed more time to review and comment on the draft regulations before
initiating the process for rulemaking. Since the September 5°'' meeting, staff has
received comments from the Board which it has integrated into the revised draft
guidelines.
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Sections 3.7 & 3.8 of the General Design Guidelines provide for the protection of
historic windows and doors. The revisions suggested in this memo are meant to
offer more specific guidance to assess the condition as well as location and
significance of a historic window or door and to help determine when
replacement is appropriate.
PROPOSED GUIDELINE CHANGES
3.7 Windows, Storm Windows, and Shutters & 3.8 Doors
Issue Discussion
Design The current guidelines discourage the replacement of
Guidelines do not windows or doors because they are crucial to the
give clear architectural character of the building, and identify windows
definition of a and doors located on the fa~ade of a building as being the
significant most important. The revisions will give further direction for
window or door. determining the significance based on the location and
importance of the window. This will be done by identifying
the location and then assessing the significance as either
"very historically important°, °historically importanY' ar
"non-historic°.
A'very impartanY window or door would be one that is
substantially intact and retains its integrity from the period of
significance. It can be further identified as very important by
its craftsmanship, style, and materiality.
An 'historically importanY feature is one that has retained
substantial integrity, and is important to the overall design or
style of the buiiding.
Lastly, a"non-historic" would classify those features that
have already been replaced, and are inconsistent in
materiality, style, pattem or proportion of the historic
window or door.
This classification system aims to provide clearer direction
far determining the significance of a window or door and
whether repair or replacement is appropriate.
Elevation A hierarchy of elevations remains as outlined in the current
hierarchy not Design Guidelines; the fa~ade is most important. The primary
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explicit in
General Design
Guidelines. elevation describes the front or principal face of a building; or
any side that faces a public right of way or open space. A
secondary elevation describes 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 no visibility from the public right of way.
By identifying the elevation of the proposed window or door
replacement, the impact on the style of the building can be
measured.
Design The Design Guidelines support replacement when windows
Guidelines do not are "too deteriorated" to repair. This creates confusion when
provide a clear determining how much deterioration constitutes a full
direction for replacement. The revisions provide a condition evaluation
determining the form and will list specific criteria for determining when
condition of a replacement is necessary. The revisions will require each
historic window window element to be analyzed individually: the sash, frame,
or door. glass, muntins, frame and sili will be assessed using a four
class system, adapted from the Secretary of the 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, 'stabilizatiori , 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 damages 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.
General Design The revisions aim to provide a clear manner by which to
Guidelines do not assess the condition of a window or door. When a window or
provide door has been determined as Class IV and a replacement is
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specifications for deemed necessary, a replacement must be approved by staff
a replacement providing information in one of two ways:
window or door. 1) Submit side-by-side comparison drawings of one vertical
and one horizontal section each of the existing window or
door and the proposed wirtdow or door. The drawings must
show the profiles of muntins, meeting rafls, sash frame, and
moldings. It should also show the window's relationship to
the existing wall.
2) Measure the individual elements and compare the existing
elements to the proposed windows or doors. This must
include glass size (width and height), muntins, casing (width
and depth), sash face, profiles, inset, pitch of sill, thickness of
sill, and how the window or door meets the existing wall.
The revised guidelines aim to provide a side by side
comparison of the existing and the proposed window or door
to assure the replacement window will not significantly
change the historic character, type or style of the house.
NEXT STEPS:
October 4-12, 2007: Final revisions to Administrative Regulations/Design
Guidelines based upon October 3 review by the
Landmarks and Environmental Advisory Boards.
Ready for review by stakeholdexs.
October 12-31: Field test Administrative Regulations/Design
Guidelines, review by the design review committee.
October 18, 2007: Publish notice of intent to make rules: file copies with
the City Clerk stating intent to adopt the rules on
September 4, 2007. Review by stakeholders begins.
November 7, 2007: Stakeholder and public comment considered by the
Landmarks Preservation Advisory Board in a public
hearing to consider adoption of Administrative
Regulations/ Design Guidelines.
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Attachment A
(Un~lerline indicates new language, strike indicates deleted language.)
3.7 Windows, Storm Windows, and Shutters
Windozns, the elements tknt surround them, nnd their relntionship to one nnother are one of the
niost iniportnnt character-defining elements of a historic structure and sltould He preserued.
Improper or insensitive trentment of ti~e euindatos on n historic struch~re can serioi~sly detracf
from its architecturnl duirncter. Tl~e relafiz~e importance of n zuindozu depends on three faetars:
flie location of tlie euindow on the builcling, tJie historic si ni ennce of tl~e znindotu, and its
eonclition. Wit2ctozos on fncades z~isihle fi•om paiblic zoat/sstreeEs, pnrtieulnrly tl~e f~a~E fn~acie, are
espeeinIl~ irr~portant. A zoindozo thnt has n hi 1tR level of }iistnric si~,nifiennce, regardless of its
location, mau also be ven~portant to the historic integrih~ of the buildin .,g The repair o historic
zuindows should be considered onl~ as n Inst resort,
GUIDELINES
Protection of Historic Windows
Retain and preserve existing historic windows, including their funcrional and
decorative features, such as frames, sashes, muntins, sills, heads, moldings,
surrounds and hardware. Because windows near the ~ fa~ade are
particularly critical to the character of historic buildings, their protection may
supercede the protection of historic windows elsewhere. In some cases, it may
be appropriate to use window elements from rear or side elevations to repair
those on the front.
Preserve original window locations; do not move windows from their historic
placement.
3 Repair rather than replace the functional and decoraHve features of ariginal
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.
that a comprel~ensive energi~ audit be to identifii areas for fmprovement. To increase a building's
Window Replacement
Tlie repair of historic ioindoeos and doors is nleua~s ~mferred as pnrt ofa reltabilitation projeet.
Research indicates that, in mosf cases, the energy efficiena/ of an old windozu cnn be increased to
that ofa t{iermnl nane renlacement bv eoenther-strivninQ. insulation of zueiQht tiockets. and the
request a landmnrk alteration eertificate to renlace zvindoms on a contributing or individualh~
.[~ il~~vzir~.al.v. n..n~....... .. L.~~ A~4.~.~:.~..n4.~.~ 4.. « «I~«4YI~~...:.~A.... L....«~~n n
.nF..... .. ..~~ .. .~~nn.~m~~} n~nH n rn4.~m.. .. ni~nH~~ F«~«~ n ....~ «. ...~....r
j~~
The location of the window(~provosed for retrofit or replacement is important
in assessing their si~nificance to a historic building. In general, the more
important the elevation where the window is located, the less likel~that retrofit
or replacement will be appropriate. ElevaHons will be categorized as iimaxy~
secondary or tertiary, using the methodology set out in Window & Door
Replacement Application and Surve~
• Renlacement of intact historic windows on orunarv elevarions is
rare~ appropriate.
• Replacement of intact historic windows on secondazy elevations is
generally inappropriate.
Replacement of intact historic windows on terfiary elevations can occur provided
it does not compromise the historic inteQritv of the buildin~
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, , . The
historic si~nificance of the windows proposed for replacement must also be
assessed. In general, the more si~nificant a window is to the building as a whole,
the less likely that a retrofit or reqlacement will be appropriate. The
a~~ropriateness of a window replacement will be determined, in part, based
upon characterization of the window as either ' Very Historically ImportanY,
'Historicall ~~portant', or'Non-Historic' (See DefiniHons).
.6 .
~r ,... ,.w,,,n,._ .,. .. ,,,a.,.,. , a:u,..,....i.. ~;.,,.a . ..,~,..., The condirion of
the window must be evaluated prior to deteruunaig whether the window or
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 existin~ condiHon for the window and identiEies
which features will be repaired and which will possibly be replaced.
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a~si~la~ If, through the Window & Door Application & Surve.~
determined that the window sashes are too deteriorated to r~air (Class III & IV~
but the window frames are salvageable, then sashes only should be replaced to
match the origin~er the Retrofit or Replacement Section.
8. rc ., . ..a,..., .w...:~ ,a:.,;a,.a ;..~,. ~,...,...,i .. ,.c ,.i ...... ... .... ~.,. _,...i ,,.,.,~ . .,.:i....
. If, throu¢h
the Window & Door Application & Survey it is deEernuned the window may be
replaced (Class III & I~, the window openin~ itself should be carefully
nreserved. It should not be made lareer or smaller to accommodate a differentlv
sized window.
9.
. If, through the
Window & Door Application & Survey it is determined the window may be
replaced (Class III & I~, the same material as was the original is most appr~
however, other materials mav be considered if the oneration. dimension, orofile, and
finish are the same.
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.....~....:..7.. C..« ..1......ti,..... .,:..:A1.. F........ ....l.l:,. ..F,.,.,.a.. t1.,. «,.7..N......1.:... ..F ....7:A.. a,.
. If a window that is divided into several panes
of ~lass must be replaced, a similar true-divided-li~ht window that matches the
dimensions, profile and detailing of the original is most a~ropriate. High
quality simulated-divided-light windows may be allowed if they maintain the
muntin size of the orieinal window. Snav-in muntins or other inauthenHc
architectural details are inappro rp iate
11. , ,
. Historic steel windows are chazacter-
defining features on some buildin~s in historic disiricts. Because windows
manufactured from other materiaLs eenerallv cannot match the thin orofiles of steel.
replacement maXnot be appropriate
12 ~Y::~~b~ ,. ••ia ; a:,....,. n,.,,. i,..,,.1~ ~...7 ..1.,...U ....a ,.,.,...« h,.t..,,.,... A,.,...,.. If LIlE
existing condition of the window(s), as docuinented by a Window & Door Surve~
indicates Class III or IV damaQe or deterioration, then the window(s) ma~
retrofitted or replaced. All retrofitted or replacement windows must match the
historic feature as closely as possible.
Windows in New Construction
.13 . Windows in additions
and new structures should reflect the window ~atterns and proportions of the
existinQ structure and the district and utilize similar materials. For elevations
visible from public streets, the relationship of solids to voids should also be
compatible.
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r~ ~
~egr~a~ Windows should be trimmed with materials similar in scale,
proporrion, finish, and character to those used traditionall~
ct,..r«e.~ .,.,a c«,,...., ~u:..,a,...,~
15 . Openin~sshould
indicate floor levels, and should not occur betcveen floors.
.16
~~'~~ a^~..-^^^'^a Synunetry or asymmetry of openin~s should be inaintained.
.17'inn.:t,...w..~+,.... ,.,.,.a ..,.. ti.,. ,.~,._..i.i,. ~~.,.....~.,...ia ti.,. ,. ,,.a .,.....:..t.:.. .w,.
. Odd window shapes such as octagons, trian~les, and
diamonds are ~enerally inappropriate.
Shutters and Storm Windows
.is
..1.. «......:«.. Cf....... . ...7.....~ ,. .,a,...:,... ~...«,.1.. .. ..1F..«....a:..,.,. L,. .. ...7.~...
..«} TAI~~.I n4~...v~ .. :~.A....... «..... L~.. ..~.~.....«..:..4..:C 4A.~ C«..«..... «...F..I. LL...
Use shutters only if appl'Opriate to the st~e 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 inappro riate.
.19 Reintroducing missing, shutters is encoura~ed if evidence of the original shutters
can be documented.
20 While shutters need not be operable, they should be sized to maintain the
appearance of operabilitv.
.21 Im rD OV1IIg the energy efficiency of older windows can often be addressed
throu~h simple repairs. Storm windows or interior energy_panels are alternafives
to window replacement. Wood storm windows are preferred. Metal storm
windows may be ap_propriate if the frames match the proparrions and profile of
the original windows and if the frames are anodized or painted so that raw metal
is not visible. Interior installation is preferred.
3.8 Doors and Storm Doors
Front doors nnd primnr~~ entrnnces are aiuong tlie most in~portant elentents of historlc bttildings.
T7~e original size nnd proportion of n front door, t{~e details of flte door, the door sa~rrottnd, nnd tlte
placen¢ent of t1~e door all contrihute to tl~e charncter of the entrnnce.
Some homeoznners mn~i zoisli to replnce ti~eir historic cloors to imprm~e energy e~n~. Resenrch
indicntes tlmt, in most cases, Iwzoever, the energt~ e ciencU of an old door can be increased to thnt
certiBrnte to replace doors an n contributing or individuallu landmnrked building, tlie steps as
outlined in the historic Windom and Door Replacement/Retro t Applicntion Guidelines
Iavailnble nt zueueu. eoml must be~'olloeoed.
GUIDELINES
1 . Whenever ~ossible,
•etain and preserve all oriQinaI doors and door openings. The location of the
door(s) ~roposed for retrofit ar replacement is important in assessing their
significance to a historic building. In general, the more important the elevation,
the less likely that replacement of a historic door will be appropriate.ElevaHons
will be categorized as prunary, secondary, or terHary, usin~ the methodolo~y set
out in the Window & Door Replacement Application and Surve~
• Replacement of intact historic doors on primary elevarions is rarely
aQ~priate.
• Replacement of intact historic doors on secondary elevaHons is ~enerally
inappropriate. Replacement of intact historic doors on terHary elevaHon can
' occur provided it does not compromise the historic integrity of the
buildin¢.
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~ i
^Pii~~at'y-2R . Tl....... F...,~,.......:«,.l,..a.~t}... ~..... ~...7 :ti.. f«..«... ..:17 1.,..,.7 : «.1.
.'I'he historic si~nificance 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 re_placement will
be a~ r~opriate. The appropriateness of a door reglacement will be determuted,
in part, based upon characterization of the door as either'Verv HistoricallX
-ImportanY,'Historically Important', or'Non-Historic'. (See Definifionsl.
_ u b~ ~
3. u:~.~~ ,.~a..«,7:.... w.. 1,.,,1...,.F~ ...7 L..,.1.,. ,. ,7.. « F....a,. .. tl...~ ..
. The condition of the door(s shall be
evaluated prior to dete+~**+in;n~ 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 surve~hat
is intended to identify the extent of deteriorarion in each window and to
determine whether the windows should be repaired, retrofitted, or re~laced. The
survey form documents the existin~ condition for the window and identifies
which features will be repaired and which will possibly be replaced.
4. n`~..:_ a.....,,,,,~ „ ...,i .a,.,._,. ....a ,a,.,... , ...i.r.,.,. ..,t,,...,..,,._ ..,...,.:i.i,.
- Y~u
. Retain and preserve the funcrional,
proportional and decorative features of a primary entrance. These features
include the door and its frame, sill, head, iamb, moldin¢s, and anv flankine
windows
,r7. TF .... ,. ....1 .7.~..« .......t 1.,. ..,....1..~,.,7 ~1.,. ..,....i..,.,.«.,...a .7,.,... ,.1.,...1,7 .......a..l. Fl,,.
....7 .. ,.1,,....1.. .. ..:l.l,. TF A..,.......,...i..a:.... ..f ~A,. ,. ~...1 A ...... :.. ....a
..:7.,1./,. ~1.,... tM.. .. ..F a1.,. .. ..7..,...«...«4 ,7....~ ..L.,...1,7 1.,. L........7 ..
. Historic hardware, hinges, locksets,
and knobs are door features that are significant and should be preserved.
6. .
` , . Repair dama~ed original
doors and door assemblies whenever possible following recognized ~reseroation
methods.
_~ rc,...,._,...,.,.....,....,.:,....,.,,a w,...i~..,... ,.:a,._..,.:..~ .,..,,..., a,,,._
~- If, through a Window & Door Ap~lication Survey replacement is
found to be appropriate, the replacement door should match the ori '~nal as
closely as possible. If documentation of the original door is not available, then
the anoearance of the revlacement door should be based on orieinal doors on
similar historic structures
.S r~,.,._,. :.. ,a,a:.:,,.,.. .~a .. ..~....~~..,.,. ..a,...ia ..,.n,.,., .w,......,...,....:,.~,. ~H,.:,.~,« ...,a
.:,a.w~ ,.r a,.,..~ :.. .w,. ,. :,.,: .... ............_,. .,...a i,._ .w,. ,~;~,..:,.. Replace wood
doors with wood doors. Although good syntheHc materials are available, the use
of historic materials is recommended.
.9 ,
^w~-~~'~~ •~ "~~°~ ..°~a '-~a:'~~--~„° If energy conservaHon and heat loss aze a
concern, consider usinQ a storm door instead of re~lacing a historic entry door.
Generally, wood storm doors are most appropriate. A metal storm door may be
a~propriate if it is sunple in desi,g,n and if the frame is anodized or painted so that
raw metal is obscured.
(Underline indicates new language, strike indicates deleted language.)
8.2 Energy Efficiency
. In 2006, Boulder's Cihi
Coiincil adovted a Climnte Action Plan to meet tl~e Kiioto Protoeol ooals ofeubstantinllv Loeue~
preserontian and energlLe cienni goals. hi tlte historic districts and on indizndi~nlhi landn~arked
ro erties it is impartant ta ensure tliat energil e eienc~ concerns nre ndciressed in znays t{uat do
riot daliu~ge or diminisli tl~e liistoric clinrncter of tl~e bailding, site or dish-ick It is reeonnnended
that before ami energil e~icienni upgrades nre nmde an instnimented energi~ nudit is conducted to
determine tl~e building's current ener~ loss.
In liistoric clzstriets, a variet~ of energy-conseming site and bttilding featiires illustrnte tlie
sensibilih~ of nn enrlier ern to clirnate and energy efficiency. Thociglitfitll~ located slinde trees
buffer residences nnd sicleioalks frorn tlte sLmt~r~er sain. Projeeting pordies proe~ide sleacted autdoor
spnce and lessen tlte fnipact of tl~e Imrsh sunlight on tlte building's interior. Opernble znindoeos
nnd sliutters allozu occupnnts to eontrol t}te introduetion of sunlight ancl breezes znitliin tl~e
bL~ildings. An understnnding of limu si~cle Itistoric feahires enlurnce ei2ergi,/ efficiei2cy is criticnl to
maxiixizing tlie energy efficiency of historic bi~ildings.
the
GUIDELINES
1 Retain and preserve the inherent enexgy-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 tradiHonal
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 direcrion.
.3 Replace deteriorated or missing wooden blinds and shutters with matching new
units sized to fit the opening. See Guideline 3916 far addirional direcHon.
.4 It is not appropriate to install solar collectors in locafions that compromise
chazacter-definin~ roofs. The installaHon of solar collectars located on a
prominenfl~visible roof may be appro rP iate provided it does not detract from the
historic character of the property or historic district.
8.3 Mechanical and Utility Facilities
GUIDELINES
1 If a new mechanical system is needed, install it so that it causes the least amount of
alteration to the building's exterior fa~ades, materials, and site features.
.2 Locate new mechanical equipment and utilities, including heatimg and au mnditioning units,
in the mostinconspicuous area, t~.sually along a building's rear facade. Screen them&om 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.
.4 It is not appropriate to install venrilators, ^^~~, 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.
Minimize the visual impacts of trash storage and service areas by screening them
from the sh•eet.
(Underline indicates new language, strike indicates deleted language.)
9. DEFINITIONS
Alignment The arrangement of objects along a straight line.
BdlCOny A railed projecHng platform found above ground
level on a buIlding.
Arth 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.
Bdlustrade 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.
Bdrgeboard A projecfing board, often decorated, that acts as trim to cover the ends of
the structure where a pitched roof overhangs a gable.
Bratket A supporting member for a projecting element or shelf, someHmes in the
shape of an inverted L and sometimes as a solid piece or a triangular
truss.
Cantileve~ A projecting beam, girder or other structural member supported only at
one end; used to support a balcony, cornice, extended eaves or any other
extension to a building or structure.
Coiumn A slender upright structure, generally consisting of a cylindrical shaft,
base, capital, and pillar: It is usually a supporHng or ornamental member
in a building.
Contributing Buildings
Those buildings built during the district's period of significance that exist
in comparaHvely original condifion, or that have been appropriately
restored, and clearly contribute to the historic significance of the district.
Such buildings may have comparible additions.
Co~tributi~g-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 alteraHon, 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.
Cornite A projection at the top of a wall or the top course or molding of a wall
when it serves as a crowning member.
Detk 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 projecHon in which this window is set.
Edve The underside of a sloping roof projecting beyond the wall of a building.
Elevdtion A mechanically accurate, "head-on" drawing of a face of a building or
object, without any allowance for the effect of the laws of perspecHve.
Any measurement on an elevaHon is in a fixed proporHon, or scale, to the
corresponding measurement of the real building.
Facdde 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
somerimes 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 Hme period. The development of
historic contexts is a foundaHon for decisions about the planning,
identificaHon, evaluafion, registration, and treahnent of historic
properties, based upon comparaHve historic significance.
Historically Important Window or poor:
The feature has retained inte~rity from the period of si~nificance and is
an integral part of the historic design or is essential to the understanding
of the architectural tXpe or style.
Historic Integrity
The degree to which a building has retained its original elements.
Human Scale
Human scale refers to the relaHonship between the d'unensions 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 far the Nafional
Register of Historic Places or for local landmark designaHon. These
buildings have a special character and historical, architectural, or
aestheric 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 recommendaHons to Council for landmark and historic district
designafions and to review proposed exterior alteraHons to Landmarks or
within landmark districts.
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 decoraHve band or strip of material with a constant profile or secHon
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 winclows or multiple windows; the central verHcal
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 poor:
Windows or doors that have been replaced, or are so extensively altered
that thep are inconsistent with the pattern, proportion or materiality of
the historic window or door.
Non-Historic windows and doors may be retrofitted or replaced.
However, the character of the retrofit or replacement should be
compatible with the historic character of the building. (See Section 3.7.13).
Pardpet A low wall or protecHve 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 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
verHcal 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 foundaHon or the topmost horizontal piece of
fi•aming at the top of a wall and where the next floar fi~aming begins or
where the roof form starts.
Post A piece of wood, metal, etc., usually long and square or cylindrical, set
upright to support a building, sign, gate, etc.; pillar; pole.
Primarv Elevation:
The front or princi~al face of a building~ or any side of a buildin~ that
faces a public ri~ht of wa~or other important public space such as a park.
Tvvically, the facade of a buildin~ is the most prominent elevarion and
will contain character defining doors and/or windows.
Protection The act or process of applying measures designed to affect the physical
condifion of a property be defending or guarding it from deteriorarion,
loss or attack or to cover or shield the property Erom danger of injuiy. In,
the case of buiidings and structures, such treahnent is generally of a
temporary nature and anricipates fuhzre historic preservation treatment;
in the case of archaeological sites, the protective measure may be
temporary or permanent.
Retrofit In a rehabilitation Qroject, the installafion 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:
Gnble roof has a pitched roof with ridge and vertical ends.
Gnmbrel roof is a variaHon of a gable roof, each side of which has a
shallower slope above a steeper one.
Hip roof has sloped ends instead of vertical ends.
Slted 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.
Sdsh A window component: see window parts.
Secondary Elevation:
^ Typically a side of a buildin~ that has less public visibility, and ma~have
fewer significant character definin~ features than on the facade.
Siding The narrow horizontal or vertical wood boards that form the outer face of
the walls in a tradiHonal wood frame house. Horizontal wood siding is
also referred to as dapboards. 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.
Sil) The lowest horizontal member in a frame or opening for a window, door,
or framed wall or parririon.
Simulated Divided Light Window
Windows that have munrins affixed to the inside and outside of the panes
of glass to simulate the look of a true divided light window.
I Soffit The underside of a structural part, as of a beam, arch, etc.
Tertiary Elevation:
The side of a building that typically 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 mulHple individual panes of glass in
the sash.
Verndculdr Buildings in indigenous styles constructed from locally available
materials following tradiHonal building practice and patterns and not
architect-designed.
Very Historically Important Window or poor
A window or door that has retained substanHal inte~ritv from the ~eriod
of siQnificance and is chazacterized bv at least one of the followinQ:
1. Defines the architectural tXpe or style of the buildin~ and without
it the azchitectural significance 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 I~ assl•
3. Was executed with a hi *~h degree of craftsmanship that would
render its restoration difficult or cosdv
4. Conveys artisHc merit through skillful integration of desi~n,
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 r~resentafive 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 Parts
The moving units of a window are known as Sasl~es and move within the
fixed Frnnie. The Snsli may consist of one large Pnne of glass or may be
subdivided into smaller panes by thin members called Muntins or Glazing
Bnrs. SomeHmes in nineteenth-century houses windows were arranged
side-by-side and divided by heavy verfical wood members called
Mullions.
o ..i
Interior
Casing
Upper Sash
Parting Stop
Check Rail
Lower Sash
Stool
Apron
Head Jamb
Sill