5A - Recommendation to City Council for amendments to Sections 9-7-7 and 9-16-1 B.R.C. 1981 CITY 0[~~ BUUI,I)h;R
PI,ANNINC I3UARll AGF,NDA ITEM
MI~:E'['1NG DATE: August 21, 2008
AGENDA "I'17'LE:
Public hearing and consideration of recommendation to City Council for proposed
amendments to Sections 9-7-7 B.R.C. 1981, `Building Height, Appurtenances" and 9-16-1
B.R.C. 1981, "General I)ctinitions." Proposed changes to the Land Use Regulations will
both remove the twenty-tive percent roof area coverage limitation for roof top solar systems
below fifty-five feet in height, and expand the maximum allowable size of "efficiency living
units."
RI~;(1[1F,S7'INC DF,FAR'1'MF;N7':
Ruth McTleyser, Acting Planning Director
Robert Ray, Land t.)sc Review Manager
Brian flolmcs, %oning Administrator
UVERVII:W
At a joint study session with Planning Board and City Council on March 13, 2008 staff
presented proposals to modify those sections of the Boulder Revised Code that relate to the
regulation of solar energy systems as "appurtenances." As directed by City Council in its
2008 work plan, staff has pursued option "A", a narrow in scope proposal intended to remove
roof area coverage limitations for rooftop solar systems.
Additionally, changes made to the definition of "floor area" in June of 1997 (Ordinance No.
5894) resulted in recently identified unintended consequences to "efficiency living units"
(ECU's); specifically, the application of the current definition of floor area results in a
reduced maximum unit sie.
Attached is a draft of proposed amendments to Sections 9-7-7 and 9-16-I.7'he most
significant modification to the land use regulations would be the elimination of a twenty-five
percent roof area coverage limitation fbr rooftop solar systems (e.g. photovoltaic panels, solar
thermal panels, etc.) on buildings less than fifty-five feet in height. The proposed
amendments also reflect changes to both the "appurtenance" and "efficiency living unit"
definitions f<nmd in 9- 16- l .
AGF:I~DA I"T1?E~9 #~A 1'a;;c I
anc~l:cltouy~ n:yu l~ultr;~c~sl.:
A. Solar Systenrs
Solar systems, as "appurtenances" and as they relate to building; height, are addressed in slightly
different ways in three separate locations within the Boulder Revised Code (B.R.C.), 1981,
which results in an unnecessary regulatory barrier to installing rooftop solar systems
(photovoltaic and solar thermal systems, etc.):
1. The city code definition of "appurtenances" (from 9-16-] B.R.C. 1981 "General
Definitions") includes "solar systems" among a longer list of rooftop mechanical
equipment that includes chimneys, ventilators, skylights, antennas, and microwave
dishes. As a part of this definition there: is reference to a twenty-five percent roof area
coverage limitation. The "appurtenances" definition does not make any reference to
building height.
2. Additionally, there is a reference in the city charter which specifically allows for "...other
mechanical appurtenances usually carried above the roof level..." to exceed the fifty-five
feet building height limit "...so long as they do not take up more than twenty-five percent
of the roof area." The charter language is silent regarding appurtenances that do not
exceed fifty-five feet.
3. Lastly, section 9-7-7 B.R.C. 1981 "Building Height, nppurlenanccs," provides some
clarity to the regulation of appurtenances beyond what is included in either the city
charter or the "appurtenances" definition. More specifically, the construction of 9-7-7
broadens the twenty-Gvc percent roof area coverage limitation such that it applies to
appurtenances (including solar systems) at any height, not only to those above fifty-five
feet.
i1t present, and in the recent past, the regulation of solar energy systems has been consistent with
~~-7-7. The result of this administration of the code is that appurtenances, including solar systems,
of all sorts and at any height, aren't allowed to exceed twenty-five percent coverage of the roof
arcs.
As a part of the joint study session with Plaro~ing Board and City Council on March 13, 2008
staff presented proposals to moth (y those sections of the land use regulations that relate to the
regulation of solar energy systems as "appurtenances." "1'he proposed ordinance presented as a
part of this memorandum reflects the selection of the narrowly-focused option "A", as directed
by City Council in its 2008 work plan.
finally, for projects with a prior discretionary review (PUD, PD, Sitc Rcvicw) the subsequent
addition of solar panels has often required a "minor modification" administrative review to
evaluate the proposal against the intent of the original approval. This additional review process
can take 2 to 3 weeks at a cost of $757.00, not including any additional design or consultant fees.
"I~his policy has been identified as another unnecessary barrier to providing solar systems. This
matter has been resolved with a departmental policy change that allows for flush-mounted
rooftop systems that do not result in an increased building height, to be pcnnittcd through the
building pern~it process. Minor modifications will no longer be required unless the proposed
system is not flush-mounted or will result in additional building height.
AGF.NllA I'TiJM #SA Pa~c 2
B. l~;fficicncy Living units
Since the early 19~Os, when the last known CLU projects arc known to have been constructed
within the city, an "efficiency living unit" has been defined as "a dwelling unit that contains a
bathroom and kitchen and does not exceed a maximum floor area of four hundred square feet."
Until the definition of"floor area" was modified in 1997 the measurement of floor area included
areas "within the outside walls". With the change in }997 the measurement method was amended
to include the thickness of exterior walls. An unintended consequence of this change to the code
is that effective living area (habitable area contained within the exterior walls of the unit) of
ELU's become proportionally smaller relative to the exterior wall thickness, a result that was
apparently neither discussed nor intended at the time the definition of "floor area" was modified.
It has been suggested this reduction may be as great as I5`% depending on the construction
method. With no new ELU's constructed since the 1980s the unintended impact to ~L11's went
unnoticed until recently when a contemporary F,L[J project, using a similar floor plan, was ti~und
to be problematic in light of the current measurement method of"floor area".
It is the opinion of staff that the impact the code change had on l:LU's was an unintended
consequence; however, given the amount of time that has since passed it is also the opinion of
staff that any new modification to the Land Use Regulations to remedy the oversight could not be
done as a part of the ongoing quarterly, non-substantive, code corrections process. As such,
rather than preparing a draft ordinance for City Council review and adoption, a change to the
"efficiency living unit" definition would need to follow the standard, public process for code;
changes that includes a public hearing before Planning Board.
"1'he staff identified two approaches to resolving the size issue for [:Ell's: the first, broader
approach, would consider making a change to the code by modifying the definition of "floor
area" such that the thickness of exterior walls would not he considered when calculating floor
area. The second approach, more specific to ELU's, considered increasing the overall maximum
sire of ELIJ's such that the effective living area would remain approximately four hundred
square feet after the inclusion of exterior wall thickness. `I'bis increase would reflect an increased
amount adequate to permit a wide variety of alternate constn~ction methods.
In the judgment of staff, the later approach is the preferred option as it is the more direct way of
remedying the issue with far less potential of creating other unintended consequences. /1 change
to the definition of "floor area" would have greater potential f~~r far reaching implications to
devclc~pment arras. the hoard, and wr~uld reyuir-c extensive analysis ;u~il public outreach-
SU1~71LVtl' O1' PROYOSI?U ORUINAN('I+,:
A. Solar Systems
"1'hc ordinance as proposed will serve to lurther the city's Climate Action ['tan by rcrnoving air
uruiecessary regulatory bamer to the installation of solar systems that result in greater than
twenty-five percent roof area coverage. 'T'his is, in part, accomplished by modifying the definition
cif "appurtenances" in 9-16-1 to remove a general reference to a twenty-five percent roof area
cxwcraac }imitation.
A(,I~;NDA ITEM #SA I'a~!e 3
The ordinance also includes changes to portions of 9-7-7 to exempt rooftop sular Systems below
fifty-five feet in height from the current roof area coverage limitation, while retaining the twcnty-
five percent roof area coverage limitations for other sorts of rooftop mechanical equipment.
Included within the changes to ~-7-7 is additional language to allow for greater flexibility, by
staff, to vary the mechanical screening requirements when such screening will interfere with the
efficient operation of the solar system.
The intended result of these changes is to allow rooftop solar systems that are greater than
twenty-five percent of the roof area, on buildings less than fifty-five feet in height, to be
permitted "by-right". A copy of the proposed ordinance is appended to this memorandum as
Attachment A.
B. I+;fficiency Living Units
"I'he proposed ordinance will restore the original intent of the code by modifying the current code
to allow for F.LU's with an effective living area within the exterior walls of four hundred square
feet within the exterior walls. "Phis is accomplished by modifying the "efficiency living unit"
definition in 9-16-1 to allow for a greater maximum floor area per 1-;LtJ. 'I'o be clear, LLU's will
technically be larger than four hundred square feet when measured per the definition of"floor
area", but as a practical matter they will have approximately four hundred square feet of effective
living area within the unit. Staff estimates that an increase from four hundred square feet to four
hundred seventy-five square feet will be adequate to accomplish this restoratiora of the original
code intent. "1'he proposed increased amount of floor area is proportionate to the amount of floor
area that is captured when adding the exterior wall thickness typical to a wide variety of
construction methods, including straw bale and adobe construction (see figures 1 and 2 below). A
copy of the proposed ordinance is appended to this memorandum as Attachment B.
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STAI+'I' k'INllIN(:S AND R~:C'()MMENDA"l'iON:
"I'he staff reconunends that Planning Board recommend approval of the proposed amendments to
Sections 9-7-7 B.R.C. 198 ] , "Building Height, Appurtenances" and 9- ] 6-1 B.R.C. 1981,
"General Definitions" (to reflect changes to both "Appurtenances" and "F~;fficiency Living
Units") to City Council.
ACF.NDA I"l'EM #SA PaQe 4
Approved fay:
/ v '
Ruth McHeyser, noting Plann'ng Director
P~antUllg D(;pal"til7ellt
A"I"I'ACH M F.NTS:
n: Proposed Ordinance for Solar System Appurtenances
E3: Proposed Ordinance for I:flicicncy Living units
AGENDA ITLM #SA YaQe S
A'I°1'ACl1MENT A
ORDINANCE NO. _ _
AN ORDINANCE AMENDING UEVELOPMi:NT REQUIRE-MENTS
REL,AT'ED TO THE INSTALLATION Oh SOLAR SYSTEMS ON
BUILDING ROOF TOPS, INCLUDING THE DIFINIfI'fON OI~
"Ai'I'URTENANCrS" 1N SEC"PION 9-16-1 "GENERAL
DEFINITIONS," B.R.C. 1981 AND AMI~.NDMF.NTS'I'O SECTION 9-
7-7, "BUILDING HF.[GH"f, APPURTENANCES," B.R.C. 1981, AND
SE"1°I'ING PORTH R1~:I,ATCD DE'T'AILS.
BE 17' ORDAINED BY T'IIE CITY COUNCIL OF THE CITY OF BOULDER,
• COLORADO:
Section 1. Section 9-1G-1, B.R.C. 1981 is amended as follows:
Section 9-16-1 General Uetinitions.
(c) The following terms as used in this title have the following meanings unless the context
clearly indicates otherwise:
"Appurtenances" means:
(I) Architectural features not used for human occupancy, consisting of spires,
belfries, cupolas or dorniers; silos; parapet walls, and cornices without windows;
and
(2) Necessary mechanical equipment usually carried above the roof level #~av~-ne
,including, without limitation,
chimneys, ventilators, skylights, antennas, microwave dishes, and solar systems,
and excluding wind energy conversion systems.
Secli+~n Section 4-7-7, I3.R.C. 1 ~~S I is amendal as I~+llow~:
9-7-7 Btiildin;~ Ilci;;ht, Appurtenances.
(a) Appurtcn;+nees: Appurtenances n+ay be added under the. t~~llowing circumstauce.5:
(l) The addition of an appurtenance to a building is permitted if it does not cause the
building height to exceed the height allowed in this section, considering, fir this
In+rpose only, the uppermost point of the appurtenance to be the uppern~ost point
o f' the roof.
(2) I'hc city manager may approve additions of appurtenances to buildings causing a
building height to exceed the maximum permitted height if the following
slarulards arc met:
AGIi+.NDA I1'l?y1 #SA Paae 6
(f1) "l~here is << llu~ctional need forthc appurtcn,urce;
(B) The functional need cam~ot be met with an appurtenance at a lesser height;
and
(L} Visible materials and colors are compatible with the building to which the
appurtenance is attached.
(3) No appurtenance may have useable floor area except for mechanical equipment
installations; have more than twenty-five percent coverage of the roof area of the
building; or be more than sixteen feet in height. I~or the purposes of this
paragraph, "coverage" means the total area enclosed by the screening and "roof
area" means outside top covering of a building which is parallel to the ground.
(4) A roof top solar system may exceed the roof area coverage requirements in
ara era ~h (a)(3) if the height such system on the building roof is under fifty-five
feet in height. The city manager may vary any screenin:; requirement for
mechanical ecpripment ifsuch screenint; will interfere with the efficient operation
of the solar system.
(45) All mechanical equipment is screened from view, regardless of the height of the
building, unless in the opinion of the city manager such screening conflicts with
the function of the mechanical equipment. The city manager will determine if the
screening of the equipment is adequate in form, materials, and color based on the
follu~~~in~~ criteria:
1 /1 j Screening is consistent with the buildinc desi~~n; colors, and materials;
(L~) Appurtenances are placed on the portion of the roof which is least visible
from adjacent streets and properties;
(C) "I'he height of the screen is the minimum appropriate to adequately screen
the mechanical equipment; and
Screening does not increase the apparent height of the walls of the
building. "I'he use of parapet walls to screen mechanical equipment is
discouraged. The height of parapet walls should be the minimum
necessary to screen mechanical cquipn~r;nt.
(S(;) A parapet wall may exceed the height. requircmuuts of~ ibis title by up to ciglrtccn
inches if the parapet is necessary to accommodate rooftop drainage or to provide
Iirc protection.
((,7) An applicant may appeal the decision of the manager under this section to the
planning board wider the procedures set forth in section 9-2-7, 'Development
Itcvicw Action." B.R.C'. 1981.
nC>?'NDA ITLM #SA Pa~c 7
(b j Landmarkecl Appurtenances: Notwithstanding any other provision oi• this section,
appurtenances of buildings landmarked under chapter 9-1 1, "Historic Preservation,"
B.R.C. 1981, •may be repaired or restored to their previous height, upon approval of the
landmarks board. If the board approves such a repair or restoration, the approval is not
effective until thirty days after the date of its approval. Promptly after the approval of the
repair or restoration, the city manager will forward to the city council a written report,
including a description of the repair or restoration and the reasons for the approval. The
manager will publish notice of the approval once in a newspaper of general circulation in
the city within thirty days after the approval is granted by the board. Upon receiving such
report and at any time before the effective date of the approval, the council may rescind
the approval and call-up the request for its consideration at a public hearing, which
constitutes a revocation of the approval.
Section 3. `T'his ordinance is necessary to protect the public health, safety, and welfare of
the residents of the city, and covers matters of local concern.
Section 4. The council deems it appropriate that this ordinance he published by title only
and orders that copies of this ordinance be made available in the office of the city clerk for public
inspection and acquisition.
INTRODUCED, READ ON FIRST READING, AND ORDERED Pl1BLISHI?D BY
'17"1'1.L ONLY this day of , 2008.
Manor
Attest:
City Clerk on behalf of the
Director of Finance and Record
READ ON SL'CONU READING, PASSED, ADOPTED, ANll URI)ERED
PUL3I,ISIIFD BY "I'ITI,I~. ONLY this _ day of _ , 20
Mayor
AllesL
City Clerk on behalf of the
L)ireetor of Finance and Record
AGENDA 1'1'1+,M #SA Pale 8
A'I"I':~Ct1iVIh;N"I' B
ORDINANCE NO.
AN ORDINANCE AMl-;NDiNG THE DEFINITION Ol~ "1?FF1C'IF.NCY
LIVING l1N[T" IN SECTION 9-16-1 "GENERAL DCFINI'I'IONS,"
B.IZ.C. 1981
BE IT ORDAINGU [3Y T~II~ CITY COUNCIL OF T1I1~. C'1'I~Y OF BOULDER,
COLORADO:
Section 1. Section 9-16-1, B.R.C. 1981 is amended as follows:
Section 9-16-1 General Definitions.
(c) The following terms as used in this title have the following meanings unless the context
clearly indicates otherwise:
"Efficiency living unit" means a dwelling unit that contains a bathroom and kitchen and does not
exceed a maximum floor area of four hundred seventy-five square feet.
Section 2. This ordinance is necessary to protect the public health, safety, and wcl tare of
the residents of~the city, and covers matters of local concern.
Section .3. Thu council dccn~s it apprupriate that this ordinance he pul~lishud by title only
and orders that copies ~~f this ordinance he made available in the office ~+f the city rlu'k ter puf~lic
inspection and acquisition.
INTRODUCED, RF,AD ON 1~IRST READING, AND ORDERED PUBLISIIF.D BY
"I'I"I'LL: ONLY this day of , 2008.
Mayor -
Attest:
City Clerk on bchal f~ of~ the _
Director of Finance and Record
AGE':NU;~ ft~t~,17 ,'ISt1 Pale 9
REAll ON SECOND RI~.ADING, 1'ASSEll, AUOP'l t~a), AND ORDERED
I'UBLISI-IrD EiY TITLE ONLY this day of _ _ , 20
Mayor - -
Attcst:
City Clerk on behalf of the
Director of Finance and Record
A(:1?NDA 1'I'EM #SA Pa~c 10