34. Bldg. code ordinance
"
ORDINANCE NO. 07-2021
DR
FT
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF
CUPERTINO AMENDING CHAPTER 16.04
OF THE CUPERTINO MUNICIPAL CODE AND ADOPTING THE
2007 CALIFORNIA BUILDING CODE VOLUMES 1 AND 2
THE CITY COUNCIL OF THE CITY OF CUPERTINO HEREBY ORDAINS that they
are adopting the 2007 California Building Code and amending Chapter 16.04 of the Cupertino
Municipal Code as follows:
. Amend Section 16.04.01 0 to read Adoption of California Building Code.
"The Building Code for the City shall be the 2007 Edition of the California Building Code,
Volumes 1 and 2 inclusive and Appendices which follow.
. Change all 2001 dates to 2007 in section 16.04.010 under APPENDIX CHAPTERS
. C - U BUILDINGS
. D - FIRE DISTRICTS
. AMEND D102.2.5 ROOF COVERING.,.,
. F - RODENT PROOFING .
. G - FLOOD-RESISTANT CONSTRUCTION
. I-PATIOCOVERS
. 2007 CALIFORNIA HISTORICAL BUILDING CODE
. 2007 CALIFORNIA EXISTING BUILIDNG CODE
. Delete Sections
. 16.04.110
. 16.04.140
. 16.04.170 thru 16.04.340
Amend 16.04.020 Section 105 ofthe Uniform Building Code to read Section 112 ofthe 2007
California Building Code and amend Section lOS-Board of Appeals: to read Section 112 - Board
of Appeals.
Amend Section 16.04.030 Section 108.7 of the Uniform Building Code to read Section 109.3.8
of the 2007 California Building Code and amend Section 10.7-0ther Inspections to read Section
109.3.8- Other Inspections
Delete and replace 16.04.080 as Roof Covering Classification.
Section 1505 of the 2007 California Building Code is amended to read: Roof coverings on all
buildings and structures hereafter erected or constructed in the City, shall be fire-retardant, and
shall comply with the standards established for Class A roofing. All recovering or replacement
roofs for existing buildings and structures shall comply the 2007 California Building Code
Section 1510 and shall be fire-retardant, and comply with the standards established for Class A
roofing. Except that a replacement or recovering of less than 10 percent of the total roof area
shall be exempt. This exception will not apply if recovering or replacement of 10 percent Of
more of the existing roof is done in any three consecutive year period.
The 2007 California Building Code, Section 1501.1 Exception is deleted.
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Ordinance No. 07-2021 2
Findings:
Local Conditions:
Climatic:
Precipitation, relative humidity, temperature and wind. These local climatic conditions affect the
acceleration, intensity and size of fire hazard ofa community. Times of little or no rainfall, of
low humidity, high temperatures and the winds experienced in this area can have a tremendous
impact upon structure fires especially when buildings are close proximity to one another.
Geographic and Topographic:
Seismic location. Seismically, the city has the San Andreas and Sargent-Berocal faults running
through the lower foothills and the Monta Vista fault system closer to the valley floor area. The
Hayward fault is just northeast of the city which would have a major effect upon the city if it
were to rupture. Adding to this threatJs the nwnber of vehicles driv~ in the city is steadily
increasing with commuters driving to and through the city either to their homes, shopping and/or
places of employment. With so many vehicles on the road at any given time during the day can
playa major role on the response time of emergency services thus greatly increasing the risk to
property and life.
Local climatic, geographic and topographic conditions impact potential damage to all structures
from earthquake and subsequent fire.
Delete and replace 16.04.110 to read:
, :"7
Amend 2007 California Building Code
Section 1614, 1614.1 and 1614.1.3 are added to Chapter 16 of the 2007 California Building
Code to read as follows: .
SECTION 1614
MODIFICATION TO ASCE 7.
1614.1 GeneraL The text of ASCE 7 shall be modified as indicated in this Section..
1614.1.3 ASCE 7, Section 12.8.1.1. Modify ASCE 7 Section 12.8.1.1 by amending
Equation 12.8-5 as follows:
Cs = Ml- 0.044 Sos I ~ 0.01
(Eq. 12.8-5)
REASONS FOR AMENDMENT/INTERPRET A TION/CLARIFICA TION:
Results from the 75% Draft of ATC-63, Quantification of Building System Performance and
Response Parameters, indicate that tall buildings may fail at an unacceptably too low of a seismic
level unless the minimum base shear level is increased to the value used in ASCE 7-02. Thus it is
recommended that the adoption of the minimum base shear is appropriate due to the recent
research in PEER and the ATC 63 project. The conclusion suggested that the reduction of the
base shear in the previous code led to 8; trend in which tall buildings had decreasing safety with
increasing height. To minimize the potential increased fire-life safety associated with such a
seismic failure of tall buildings, this proposed modification increas~ the minimum base shear
level to be consistent with previous edition of the building codes. The propose amendment to the
current ASCE 7 is very well supported by the engineering community. Both SEAOSC and other
structural engineer organizations from the state level are in support of adopting the revised
minimum base shear.
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Ordinance No. 07-2021 3
FINDINGS:
Local Geological Conditions - The Bay Area region is a densely populated area having buildings
constructed over and near a vast array of fault systems capable of producing major earthquakes,
including but not limited to the recent 1989 Lorna Prieta Earthquake. Due to the large numbers
of tall buildings in this region as well as the increased fire-life safety associated with such a
seismic failure, the proposed modification to have a higher minimum base shear consistent with
previous edition of the building codes need to be incorporated into the code to assure that new
buildings and additions to existing buildings are designed and constructed in accordance with the
scope and objectives of the International Building Code.
Delete 16.04.140
Delete and replace 16.04.170 to read:
Section 1614, 1614.1 and 1614.1.7 is added to Chapter 16 of the 2007 California Building
Code to read as follows:
SECTION 1614
MODIFICATION TO ASCE 7.
1614.1 General. The text of ASCE 7 sha1l6'e modified as indicated in this Section.
1614.1.7 ASCE 7, Section 12.12.3. Replace ASCE 7 Section 12.12.3 as follows:
12~12.3 Minimum Building Separation. All structures shall be separated from
adjoining structures. Separations shall allow for the maximum inelastic response
displacement (6M)' ~M shall be determined at critical locations with consideration
for both translational and torsional displacements of the structure as follows:
6M==CdOmax
(Equation 16-45)
where ~max is the calculated maximum displacement at Level x as define in ASeE
7 Section 12.8.4.3.
Adjacent buildings on the same property shall be separated by at least a distance
6MT, where
~ MT == .J( ~MI i + ( 6M2 i
(Equation 16-46)
and.6MI and ~M2 are the maximum melastic response displacements of the
adjacent buildings.
Where a structure adjoins a property line not common to a public way, the
structure shall also be set back from the property line by at least the displacement,
6M, of that structure.
Exception: Smaller separations or property line setbacks shall be permitted when
justified by rational analyses.
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Ordinance No. 07~2021 4
REASONS FOR AMENDMENT/INTERPRETATION/CLARIFICATION:
Section 12.12.3 of ASCE 7-05 incl~ding Supplement No.1 does not provide requirements for
separation distances between adjacent buildings. Requirements for separation distances between
adjacent buildings, not structurally connected, were included in previous editions of the mc and
UBC. However, when ASCE 7-05 was adopted by reference for mc 2006, these requirements
were omitted. In addition, ASCE 7-05 defines (ox) in Section 12.8.6 to refer to the deflection of
Level x at the center of mass. The actual displacement that needs to be used for building
separation is the displacement at critical locations with consideration of both the translational
and torsional displacements. Thes~ values can be significantly different. .
This code change f1lls the gap of this inadvertent oversight in establishing minimum separation
distance between adjoining buildings which are not structurally connected. The purpose of.
seismic separation is to permit adjoiniJ).g buildings, or parts thereof, to respond to earthquake
ground motion independently and thus preclude possible structural and non-structural damage
caused by pounding between buildings or other structures.
Reference:
1. IBC 2000 Section 1620.3.6, Building Separations; IBC 2003 Section 1620.4.5, Building
Separations;
2. "Recommended Lateral Force Requirements and Commentary, - Section CI08.2.11,
Building Separations," Structural Engineers Association of California, Sacramento, CA, 1999
Edition' ' :.,
,
3. CBC 2002 (UBC 1997) Section 1630.9.2, Determination of ~M; Section 1630.10.1, General;
and Section 1633.2.11, Building Separations.
FINDINGS:
Local Geological Conditions - The greater Bay Area region is a densely populated area having
buildings constructed over and near a vast array of fault systems capable of producing major
earthquakes, including but not limited to the recent 1989 Loma Prieta Earthquake. The seismic
separation is necessary to permit adjoining buildings, or parts thereof, to respond to earthquake
ground motion independently and preclude possible structural damage due to pounding between
buildings and other structures. The need to incorporate this modification into the code will help
to assure that new buildings and additions to existing buildings are designed and constructed in
accordance with the scope and objectives of the International Building Code.
Delete and replace 16.04.180 to read:
Section 1908.1 is amended to read as shown below and Section 1908.1.17 is added to Chapter 19
of the 2007 California Building Code to read as follows:
1908.1 General. The text of ACI 318 shall be modified as indicated in Sections 1908.1.1
through 190&.1.16 1908.1.17.
1908.1.17 ACI 318, Section 14.8. Modify ACI 318 Section 14.8.3 and 14.8.4 replacing
equation (14-7), (14-8) and (14-9).
1. Modify equation (14-7) of ACI 318 Section 14.8.3 as follows:
Icrshall be calculated by Equation (14-7), and Ma shall be obtained by iteration of
deflections.
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Ordinance No. 07-2021
I = Es (A + p., ~)(d _ C)2 + lwc3
cr E s f 2d 3
c y
5
(14-7)
and the value EslEe shall not be taken less than 6.
2. Modify ACI 318 Sec~ 14.8.4 as follows:
14.8.4 - Maximum out-of-plane deflection, ~S~ due to service loads~ including P~ effects~
shall not exceed 1J150. IfMa, maximum moment at mid-height of wall due to service
lateral and eccentric loads, including P ~ effects~ exceed (2/3) Men ~s shall be calculated
by Equation (14-8): ~.
2
2 Ma -3Mer ( 2 )
/).s = -~cr + 2 An --ACT
3 M --M /3
II 3 CI'
(14-8)
IfMa does not exceed (2/3) Mcr,~s shall be calculated by Equation (14-9):
. ~,1t
l1, ~(~:}a
(14-9)
where:
2
Acr = 5M crle
48EJ g
REASONS FOR AMENDMENT/INTERPRET ATION/CLARIFICA TION:
Section 14.8 was introduced in ACI 318-99 based on requirements of the Uniform Building
Code and experimental research and on the basis that design of slender wall must satisfy both
strength and serviceability requirements. ACI 318-05 provision was found to grossly
underestimate service load deflection. This update reduces the differences in serviceability
provisions. The revision will essentially replace equations (14-8) and (14-9) with two new
equations to reflect the UBC procedure for service load out-of-pane deflection. The proposed
revision will be included in ACI 318-08.
FINDINGS:
Local Geological Conditions ~ The greater Bay Area region is a densely populated area having
buildings constructed over and near a vast array of fault systems capable of producing major
earthquak:es~ including but not limited to the recent 1989 Lorna Prieta Earthquake. The proposed
modification to ensure that the design of slender wall must satisfy both strength and
serviceability requirements need to be incorporated into the code to assure that new buildings
and additions to existing buildings are designed and constructed in accordance with the scope
and objectives of the International Building Code.
Delete l6.04.190~ 16.04.200, 16.04.210, 16.04.220~ 16.04.240~ 16.04.250, 16.04.260~ 16.04.270,
16.04.280~ 16.04.290~ 16.04.300, 16.04.31 0, 16.04.320~ 16.04.330.
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Ordinance No. 07-2021
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Amend 16.04.340 and replace with:
Conventional Construction Provisions (Bracing).
Modify existing CBC Section.2308.9.3 to read as follows:
(Geological II)
2007CBC Section 2308.9.3, Items 5 & 7 are amended as follows.
Delete 2007 CBC Section 2309.9.3, It~m 5 which allows the use of gypsum board.
Amend 2007 CBC Section 2308.9.3, Item 7 as follows:
Portland cement plaster on studs spaced 16 inches on center installed in accordance with Section
2510 is limited to one-story structures of R-3 and U occupancies.
. .
INTRODUCED at a regular meeting of the City Council of the City of Cupertino
the 20th day of November 2007 and ENACTED at a regular meeting of the City Council of the
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City of Cupertino the 18th day of December 2007, by the following Vote:
Vote:
Members of the City Council
Ayes:
Noes:
Absent:
Abstain:
A TrEST:
APPROVED:
City Clerk
Mayor, City of Cupertino
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