HomeMy WebLinkAboutPH 1 ROOF COVER REQ 09-07-93AGENDA_-.
DATE:
SEPTEMBER ?,' 1993
~'~-PUBLIC HEARING NO. 1 -7-93
TO:
FROM:
SUBJECT:
WILLIAM A. HUSTON, CITY MANAGER
COMMUNITY DEVELOPMENT DEPARTMENT
ORDINANCE NO. 1115- ROOF COVERING REQUIREMENTS
RECOMMENDATION
It is recommended that the City Council take the following actions:
Adopt Resolution No. 93-84 setting forth findings in
conformance with State law for certain local modifications
and changes to the Uniform Building Code.
2. Hold first reading of Ordinance No. 1115, by title only.
3. Introduce Ordinance No. 1115.
FISCAL IMPACT
The modification of roof covering requirements does not have fiscal
impact upon the City.
BACKGROUND
At the July 6, 1993 City Council meeting, staff was directed to
prepare a draft ordinance and resolution and to provide notice of
a public hearing regarding the possibility of increasing the
minimum fire resistive Classification of roofing materials
installed in the City.
The City regulations currently require a minimum of Class "C"
roofing with the exception of hillside districts where Class "A"
roofing is required.
Following the July 6th City Council meeting, the Building Official
received phone calls from several homeowners associations regarding
the proposed change in roofing regulations. The .comments made
indicated no support for requiring all Class "A" roofing. The
associations who called did indicate their willingness to
participate in a public hearing for the consideration of requiring
Class "B" roofing as the minimum standard.
The testing criteria for obtaining a Class "B" rating are more
stringent than those for Class "C". Therefore, the Class "B" roof
can be expected to provide a higher level of fire resistance.
Ordinance No. 1115
Roof Covering Requirements
Page two
Uniform Building Code Section 3203 includes the following
components in the roof covering assembly which is assigned a roof
covering classification; roof deck, underlayment, interlayment,
insulation, and coverings. All roofing materials are required to
be installed in accordance with the manufacturer's installation
instructions. The combination of these two requirements can result
in additional costs for reroofing existing structures when a Class
"B" classification is required. A significant number of existing
buildings have roof structures that are sheathed with spaced
sheathing. Spaced sheathing is a method of roof sheathing that
utilizes l"x 6" boards with 4" to 5" gaps between the boards. The
roofing material is then attached to the spaced boards. Many of
the Class "B" roofing'products are required to be attached to roof
decks sheathed with a minimum of 1/2" thick plywood in order to
obtain ~the "B" classification.
When 1/2" plywood is required as a part of the Class "B" roof
covering assembly and the building has spaced sheathing, the
property owner is then faced with the cost of tearing off the old
roofing material and sheathing the roof with'l/2'' plywood.
An example of the differences between Class "C" and Class "B" when
reroofing an existing residence with spaced sheathing and non-rated
wood shingles are as follows:
To obtain Class "C" with the new roof, the existing spaced
sheathing and non-rated shingles may remain and new Class "C" rated
shingles could be applied directly over the exiSting roofing.
To obtain Class "B" withithe new roof, the' existing shingles must
be removed, 1/2" plywdod must be installed over the spaced
sheathing, a .002 polyethylene coated steel foil is installed,'and
Class "B" rated shingles are then installed.
The cost difference between a Class "C" and Class "B" roof can be
significant based upon the existing conditions. Eight cities in
Orange County currently~:require a Class "B" roofing and twenty
cities require Class "C"'
_
A resolution and ordinanCe have been prepared that would establish
Class "B" as the minimum roofing classification for the City.
Rick Brown,
Building Official
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Christine Shingleton.~/
AssiStant City Mang~
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ORDINANCE NO. llm5
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY
OF TUSTIN AMENDING SPECIFIC SECTIONS OF
ARTICLE 8 OF THE TUSTIN CITY CODE - BUILDING
REGULATIONS.
The city Council of the City of Tustin does hereby ordain
as follows:
a ~
Subsection (f) of Section 8103 of Chapter 1 of
Article 8 of the Tustin City Code, is hereby
repealed in its entirety. A new Subsection (f) is
added to read as follows:
,,(f) Section 3203 is amended to read as follows:
Section 3203. Roof Covering Requirements. The
roof covering on any structure regulated by this
code shall be as specified in Table No. 32-A and as
classified in Section 3204.
Exception: Group R and M occupancies shall have a
minimum roof covering of Class "B", except in
hillside areas where a minimum Class "A" roof
covering shall be used.
The roof covering assembly includes the roof, deck,
underlayment, interlayment, insulation and covering
which is assigned a roof covering classification."
PASSED AND ADOPTED at a regular'meeting of the City
Council of the City of Tustin held on the day of
, 1993.
JIM POTTS
Mayor
MARY WYNN
City Clerk
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RESOLUTION NO. 93-84
A RESOLUTION OF THE CITY COUNCIL OF
THE CITY OF TUSTIN, SETTING FORTH
FINDINGS WITH RESPECT TO LOCAL
CONDITIONS WITHIN THE CITY OF TUSTIN
WHICH MAKE CERTAIN MODIFICATIONS AND
CHANGES TO THE UNIFORM BUILDING CODE
REASONABLY NECESSARY FOR HOUSING
OCCUPANCIES
WHEREAS, Health and Safety Code Section 17958
provides that if the City of Tustin ("City") does not
adopt ordinances and regulations imposing the same or
modified or changed requirements as are contained in the
regulations adopted by the State pursuant to Health and
Safety Code Section 17922, then the regulations published
pursuant to Section 17922 become applicable to the City;
and
WHEREAS, the State of California is mandated by
Health .and Safety Code Section 17922 to adopt by
reference the same requirements as are contained in the
most recent edition of the Uniform Building and Housing
Codes of the International Conference of Building
Officials, the Uniform Plumbing Code of the International
Association of Plumbing and Mechanical Officials, and the
National Electrical Code of the National Fire Protection
Association (hereinafter referred to collectively as
"Codes"; and
WHEREAS, Health and Safety Code Section 17958.5(a)
permits the City to make modifications or changes to the
Codes, which are reasonably necessary because of local
climatic, geological or topographic conditions; and
WHEREAS, Health and Safety Code Section 17958.7
provides that before making any modifications or changes
to the Codes, the City Council shall make an express
finding that such changes or modifications are reasonably
necessary because of local climatic, geological or
topographic conditions; and
WHEREAS, the Community Development Department has
recommended that changes and modifications be made to the
codes and have advised that certain changes and
modifications to the Uniform Building Code, 1991 Edition,
are reasonably necessary due to local conditions within
the City and are reasonably necessary to safeguard life
and property within the City.
NOW, THEREFORE, BE IT RESOLVED by the City Council
of the City of Tustin as follows:
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Resolution No. 93-84
Page 2
The following changes and modifications to the Uniform
Building Code, '1991 Edition, as recommende~ by the City
Building Official, are hereby .found to be reasonably
necessary due to the following local conditions.
A. Uniform Building Code Section 3203 is amended to
require that roofing materials have a minimum of a Class
"B" rating, for Group R and M occupancies. A minimum of
Class "A" roofing material is required for designated
hillside districts for the following reasons:
Climatic conditions:
1. The City is located in a semi-arid
Mediterranean type climate.
It annually experiences extended periods of
high temperatures with · little or no
precipitation. Hot dry foehn (Santa Aha
wind), which may reach speeds up to 70 m.p.h,
is also common to the City. These climatic
conditions cause extreme drying of vegetation
and common building materials and predispose
the area to large destructive fires
(conflagration)·
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The climate alternates between extended
periods of drought and brief flooding
conditions. Water demand in this densely
populated .area far exceeds the. quantity
supplied by natural precipitation; and
although the population continues to grow the
already taxed water supply does not.
California is projected to increase in
population by nearly 10 million over the next
quarter of a century with 50 percent of that
growth centered in Southern California.
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These dry climatic conditions and winds
contribute to the rapid spread of even small
fires originating in high density housing or
vegetation. These fires spread very quickly
and create a need for increased levels of fire
protection.
The added protection of more fire resistive
roofing materials will help to control the
spread of fire and lessen the impacts of roof
fires on property and persons.
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Resolution No. 93-84
Page 3
Topographical conditions:
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Traffic and circulation congestion is an
artificially created, obstructive
topographical condition, which is common in
the City.
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These topographical conditions combine to
create a situation which places fire
department response time to fire occurrences
at risk, and makes it necessary to provide
fire resistive roofing materials that will
slow or stop the spread of fire from roof to
roof and provide for the reasonable protection
of occupants and property.
Geological conditions:
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The City is located in an area of high seismic
activity, seismic zone 4. The Newport-
Inglewood Fault, located west of the City,
poses the greatest hazard to life and
property.
Geologic studies indicate that this fault is
capable of generating a maximum credible 7.5
magnitude earthquake. Because of the City's
degree of urbanization and close proximity to
a major fault, the risk of structural damage
and loss of life 'due to ground shaking is
considerable.
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Major earthquakes are always accompanied by
disruption of traffic flow and fires.
During a major earthquake fire department
resources would be extremely taxed and the
ability to respond to fires would be
complicated and in some cases impossible due
to disrupted traffic flow in what is already a
congested area. Fire resistive roofing
materials will help to mitigate the spread of
fire under such circumstances.
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Resolution No. 93-84
Page 4
PASSED AND ADOPTED at a regular meeting of the Tustin
City Council, held on the day of ,
1993.
JIM POTTS
Mayor
MARY E. WYNN
City Clerk
STATE OF CALIFORNIA )
COUNTY OF ORANGE )
CITY OF TUSTIN )
SS
CERTIFICATION FOR RESOLUTION NO. 93-84
MARY E. WYNN, City Clerk and ex-officio Clerk of the City
Council of the City of Tustin, California, does hereby
certify that the whole ~umber of the members of the City
Council of the City of Tustin is 5; that the above and
foregoing. Resolution No. 93-84 was duly and regularly
introduced, passed, and adopted at a regular meeting of
the Tustin City Council, held on the day of
, 1993.
COUNCILMEMBER AYES:
COUNCILMEMBER NOES:
COUNCILMEMBER ABSTAINED:
COUNCILMEMBER:ABSENT:
MARY E. WYNN
City Clerk
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