HomeMy WebLinkAboutRPT 3 FIRE RETARD 07-06-93AG EN D-/L--.
REPORTS NO. 3
.-' ;'_~ 7-6-93
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DATE:
JULY 6, 1993
TO: - WILLIAM A. HUSTON, CITY MANAGER
FROM: C0MMU~ITY ~EVEI~DPMENT DEPARTMENT
SUMJECI: FIRE RETARD;tNT ROOFING
RECOMMENDATION:
Receive and file
FISCAL IMPACT:
The modification of the roof covering requirements does not have
fiscal impact upon the City.
BACKGROUND:
The Community Development Department provided the City Council with
a staff report on fire retardant wood shake and shingle roofing
material at the May 3, 1993 City Council meeting. A copy of the
staff report is included as Attachment "A" to this report.
During the recent discussions regarding the adoption of the Uniform
Fire Code, some additional qUestions were raised regarding the
impacts of increasing the City's fire retardant roofing
requirements and the impacts of any changes in the regulations on
property owners when reroofing a building or a portion of a
· building. Additionally, the impact of any change in regulations on
new development in East Tustin must be considered.
Our current tuilding ordinance requires a minimum of class "C"
roofing on residential properties except in hillside districts
where class "A" roofing is required. In the new development in
East Tustin, all roofs are tile or asphalt shingles, which are
classified as class "A" roofing by Uniform Building Code, Section
3204(a). Therefore, a change in the roofing requirements, would
not require any change in the roofing materials used in the new
development in East Tustin. Staff has talked with the Building
Industry Asscciation (BIA) regarding this issue. The BIA has
indicated tha5 they would not oppose a change in regulations,
provided thaZ it did not impose additional requirements for the
builders in East Tustin. Any change in roofing regulations would
impose new requirements, but would not require a change from the
current practice of installing tile or asphalt shingle roofing in
East Tustin.
July 6, 1993
Page two
Reroofing of existing residential buildings occurs in two primary
categories. These categories are single family and multi-family
dwellings.
Multi-family dwellings typically receive a complete reroof when the
useful life of the existing roofing has expired. At the time of
reroof, the new roof must comply with the fire retardant
classification required by the building code in effect at the time.
Under our current regulations, this would require that the new
roofing have a minimum of a class "C" rating.
Single family dwellings have two main activities that involve
reroofing. The first is, new roofing associated with a room
addition or expansion of an existing residence. Under this
scenario, all new roofing is required to have a class "C" rating,
but the existing roofing on other portions of the house would be
allowed to remain as non-rated roofing until its useful life
expired.
The second scenario at a Single family dwelling involves no
expansion in the size or configuration of the home, but only the
replacement of the roofing. When reroofing an existing single
family dwelling, the new roofing must have a minimum of a class "C"
rating.
Roofing maintenance occurs on both multi-family and single family
dwellings. When maintaining existing roofing, repairs may be made
with the type of material originally used. The building code
assigns the Building Official the task of determining what
constitutes maintenance and what constitutes new work. The
Building Official views incidental maintenance for the stopping of
· leaks as a minor repair when it does not require removal and
replacement of roofing or when the removal and replacement of
roofing is limited to a small portion of the roof (typically 1
square or a 10'xl0' area). Removal and replacement of larger areas
of roofing are considered as new work and are required to meet
current regulations with regards to roofing classification.
The primary hazard associated with the existing roofing involves
non-rated shake and shingle roofs. This untreated cedar or redwood
material is readily flammable and develops flying brands which can
spread fire to adjacent properties. Current technology has made
available wood shakes and shingles with class "C" and class "B"
ratings. For property owners that wish to maintain the shake or
shingle appearance of the roof, they. may reroof with class "C" or
class "B" shakes or shingles.. Additionally, a structure that
currently has a.wood shake or shingle roof may be reroofed with an
asphalt shingle roof. Asphalt shingle roofs have a class "A"
rating.
July 6, 1993
Page three
There are also many proprietary roofing products with "C", "B", and
"A" classifications that may be used to replace wood shakes or
shingles. Reroofing an existing wood shake or shingle roof with
clay or concrete tile roofing is not possible without reworking the
roof structure to accommodate the additional weight. This process
involves considerable additional costs.
The costs for materials most commonly used for reroofing are as
follows:
Class "A" Asphalt Shingles
Non-rated Shakes (not allowed)
Class "C" Shakes
Class "B" Shakes
$23 - $58 per square (10'xl0')
$100 - $135 per square (10'xl0')
$140 - $160 per square (10'xl0')
$150 - $185 per square (10'xl0')
Assuming a typical single family dwelling at 26 squares or 2,600
square feet of roof area, the cost difference for the different
rated roofing materials would be as follows:
Class "A" Asphalt Shingles
Non-rated Shakes (not allowed)
Class "C" Wood Shakes
Class "B" Wood Shakes
$589.00 - $1,508.00
$2,600.00 - $3,510.00
$3,640.00 - $4,610.00
$3,900.00- $4,810.00
Due to the rising costs in wood products and the additional costs
associated with the fire treating of shakes and shingles, the City
issues permits for very few wood shake or shingle reroofs.
The fire retardant classification of roofing is based upon test
criteria which vary significantly between classifications. A
summary of roofing test criteria is included in Attachment "B".
A summary of roofing classification requirements for Orange County
cities is included in Attachment "C".
The 1994 editions of the Uniform Building Codes will be available
for local review, modification, and adoption in the spring of 1995.
During the review and modification period, we may establish more
restrictive roofing standards when substantiated by' appropriate
findings based upon local geography, topography, or meteorology.
Modifying building codes on a triennial basis is consistent with
State law. If the City Council desires to change the current
roofing regulations prior to the next code adoption cycle, this.may
only be done as an emergency amendment to the code. The process
for adopting an emergency amendment-also requires the documentation
of findings to establish the local needs for the increased
requirements.
July 6, 1993
Page four
Staff does not encourage revising the roofing requirements outside
of the normal review and adoption cycle that occurs every three
years.
Rick Brown
Building Official
Christine Shingleton~
Assistant City Manager
ccrepor t: roof2, rb: hm
DATE:
MAY 3, 1993
· TTACHMENT "A"
Inter-Com ....
TO:
FROM:
SUBJECT:
WILLIAM A. HUSTON, CITY MANAGER .
COMMUNITY DEVELOPMENT DEPARTMENT
FIRE RETARD]tNT WOOD SHAKE AND SHINGLE ROOFING MATERIALS
RECOMMENDATION
Receive and file
FISCAL IMPACT
There is no fiscal impact to the City. No additional inspections
are required for the inspection of fire resistive roofing.
BACKGROUND
At the January 19, 1993 meeting of the City Council, Council member
Thomas requested a report on fire retardant wood shake and shingle
roofs.
Roofing products are assigned a fire retardant classification based
upon independent testing in accordance with Uniform Building Code
Standard No. 32-7. The testing is intended to indicate the
characteristics of roof coverings when exposed to fire. UBC
Standard No. 32-7 establishes four classes of roofing material,
with Class A having the highest level of fire resistance and
· nonrated roofing (i.e. untreated wood shakes and shingles) having
no tested fire resistive characteristics.
A summary of fire retardant roofing classifications is as follows:
Class A roof coverings are effective against severe fire test
exposures. Under such exposures, roof coverings of this class are
not readily flammable, afford a fairly high degree of fire
protection to the roof deck, do not slip from position, and are not
expected to produce flying brands.
Class B roof coverings are effective against moderate fire test
exposures. Under such exposures, roof coverings of this class are
not readily flammable, afford a. fairly high degree of fire
protection to the roof deck, do not slip from position, and are not
expected to produce flying brands.
May 3, 1993
Page two
Class C roof coverings are effective against liqht fire test
exposures. Under such exposures, roof coverings of this class are
not readily flammable, afford a fairly high degree of fire
protection to the roof deck, do not slip from position, and are not
expected to produce flying brands.
Nonrated roof coverings are untested for fire resistance or have
failed to pass fire exposure testing.
Requirements for roof coverings are contained in the Uniform
Building Code (UBC) Chapter 32. UBC table 32-A establishes minimum
roof classes. This table has been amended by the City of Tustin to
require a minimum of Class C roofing for residential buildings,
except in hillside areas where a minimum of Class A roof covering
shall be used.
State Assembly Bill No. 2131 will require that, on or after July 1,
1995, all new roofs shall have a minimum of Class C rating. Also,
all reroofs involving 50% or more of the existing roof within a
one-year period will require the installation of Class C roofing.
The City currently requires fire resistive roofing. Our current
roofing requirements are also consistent with the upcoming
requirements from the State.
The 1994 editions of the Uniform Building Codes will be available
for local review, modification, and adoption in the spring of 1995.
During the review and modification period, we may establish more
restrictive roofing standards when substantiated by appropriate
findings based upon local geography, topography, or meteorology.
Modifying Building Codes on a triennial basis is consistent with
· State law. If the Council desires to change ~he current roofing
.regulations prior to the next Code Adoption Cycle, this may be done
as an Emergency Amendment to the Code. The process for adopting an
Emergency Amendment also requires the documentation of findings to
establish the local need for the increased requirements.
Wood shakes and Shingles are available in nonrated, Class C, and
Class B categories. Our current Building Ordinance does not allow
for the use of nonrated roofing materials. All wood roofs are
required to be a minimum of Class C. Class C and Class B wood
shakes and shingles have fire retardant chemicals pressure cooked
into the wood fiber at the factory. Field applications of fire
retardant chemicals are not accepted for compliance with Class C or
B requirements.
May 3, 1993
Page three
The following cities in Orange County have fire resistive roofing
requirements that are more stringent than the UBC:
CiTY
MINIMUM ROOFING CLASSIFICATION
Anaheim A & ~B
Brea C
Buena Park C
Costa Mesa C
Cypress C
Fullerton C
Garden Grove C
Huntington Beach C
Irvine C
Laguna Beach B
La Habra C
La Habra Heights C
La Palma C
Los Alamitos C
Newport Beach C
Orange A
Placentia C
Santa Ana C
San Clemente B
San Juan Capistrano C
Seal Beach C
Stanton C
Tustin A & C
Villa Park C
Westminister B
Yorba Linda C
Rick Brown
Building Official
Christine Shingleton
Assistant City Manager
R8: roof. mem: hm
ATTACHMENT "B"
Excerpts from Underwriters Laboratory Standard 790
Fire Resistive Tests for Roof.Covering Materials
Intermittent Flame: The roofing material is subjected to
intermittent flames as follows:
Temperature (F)
Flame on (minutes)
Flame off (minutes)
Cycles
A B C
1400 1400 1300
2 2 1
2 2 2
15 8 3
Spread of Flame: The edge of the roofing material is subjected to
flames for the time specified. The fire can not spread to the
opposite side of the deck.
A B C
Minutes 10 10 4
Burning Brand: A piece of burning wood (brand) is placed on the
roofing material. The fire can not spread to the deck.
Weight of brand (gm)
A B C
2000 500 10
The following test applies only to treated wood shingles and
shakes:
Flying Brand: An air current is applied to the roofing material o
determine if flying brands develop.
\
Air current speed (mph)
A B C
24 18 12
ATTACHMENT "C"
summary of Roofing Requirements for Orange County C~t~es
CITY
MINIMUM ROOFING CLASSIFICATION
Anaheim A & B
Brea C
Buena Park C
Costa Mesa C
Cypress C
Fullerton C
Garden Grove C
Huntington Beach C
Irvine C
Laguna Beach B
La Habra C
La Habra Heights C
La Palma C
Los Alamitos C
Mission Viejo B
Newport Beach C
Orange A
Placentia C
Santa Ana C
San Clemente B
San Juan Capistrano C
Seal Beach C
Stanton C
Tustin A & C
Villa Park C
Westminister B
Yorba Linda C