SECTION
902
FIRE CLASSIFICATION
902.1
Roofing
covering materials.
Roofs shall be covered
with materials as set forth in Sections 904 and 905. Class A, B or C roofing
shall be installed in jurisdictions designated by law as requiring their use or
where the edge of the roof is less than 3 feet (914 mm) from a lot line. Class
A, B and C roofing required by this section to be listed shall be tested in
accordance with UL 790 or ASTM E108.
Exceptions:
1.
Class A roof
assemblies include those with coverings of brick, masonry and exposed concrete
roof deck.
2.
Class A roof assemblies include ferrous or copper
shingles or sheets, metal sheets and shingles, clay or concrete roof tile, or
slate installed on noncombustible decks.
3.
Class A roof
assemblies include minimum 16 ounces per square foot copper sheets installed
over combustible decks.
4.
Class A roof assemblies include slate installed over
underlayment over combustible decks.
902.2
Fire-retardant-treated shingles and shakes.
Fire-retardant-treated wood shakes and shingles shall
be treated by impregnation with chemicals by the full-cell vacuum-pressure
process, in accordance with AWPA C1. Each bundle shall be marked to identify
the manufactured unit and the manufacturer, and shall be labeled to identify
the classification of the material in accordance with the testing required in
Section 902.1, the treating company and the quality control
agency.
902.3
Building-integrated photovoltaic product.
Building-integrated photovoltaic products installed as
the roof covering shall be tested, listed and labeled for fire classification
in accordance with Section 902.1.
902.4
Rooftop-mounted photovoltaic panel systems.
Rooftop-mounted photovoltaic panel systems installed on
or above the roof covering shall be tested, listed and identified with a fire
classification in accordance with UL 1703 and UL 2703. Class A, B or C
photovoltaic panel systems and modules shall be installed in jurisdictions
designated by law as requiring their use or where the edge of the roof is less
than 3 feet (914 mm) from a lot line.
SECTION
905
REQUIREMENTS FOR ROOF
COVERINGS
905.1
Roof covering application.
Roof coverings shall be applied in accordance with the
applicable provisions of this section and the manufacturer's installation
instructions. Unless otherwise specified in this section, roof coverings shall
be installed to resist the component and cladding loads specified in Table
301.2(2), adjusted for height and exposure in accordance with Table
301.2(3).
905.1.1
Underlayment.
Underlayment for asphalt shingles, clay and concrete
tile, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type
shingles, wood shingles, wood shakes, metal roof panels and photovoltaic
shingles shall conform to the applicable standards listed in this chapter.
Underlayment materials required to comply with ASTM D226, D1970, D4869 and
D6757 shall bear a label indicating compliance to the standard designation and,
if applicable, type classification indicated in Table 905.1.1(1). Underlayment
shall be applied in accordance with Table 905.1.1(2). Underlayment shall be
attached in accordance with Table 905.1.1(3).
Exceptions:
1.
As an alternative,
self-adhering polymer-modified bitumen underlayment complying with ASTM D1970
installed in accordance with both the underlayment manufacturer's and roof
covering manufacturer's instructions for the deck material, roof ventilation
configuration and climate exposure for the roof covering to be installed, shall
be permitted.
2.
As an alternative, a minimum 4-inch-wide (102 mm) strip
of self-adhering polymer-modified bitumen membrane complying with ASTM D1970,
installed in accordance with the manufacturer's installation instructions for
the deck material, shall be applied over all joints in the roof decking. An
approved underlayment for the applicable roof covering for maximum ultimate
design wind speeds, Vult, less than 140 miles per hour shall be applied over
the entire roof over the 4-inch-wide (102 mm) membrane strips.
3.
As an alternative,
two layers of underlayment complying with ASTM D226 Type II or ASTM D4869 Type
III or Type IV shall be permitted to be installed as follows in 3.1 -
3.4:
3.1.
Apply
a 19-inch-wide (483 mm) strip of underlayment parallel with the eave. Starting
at the eave, apply 36-inch-wide (914 mm) strips of underlayment felt,
overlapping successive sheets 19 inches (483 mm). End laps shall be 4 inches
(102 mm) and shall be offset by 6 feet (1829 mm).
3.2.
The underlayment
shall be attached with corrosion-resistant fasteners in a grid pattern of 12
inches (305 mm) between side laps with a 6-inch (152 mm) spacing at side and
end laps.
3.3.
Underlayment shall be attached using metal or plastic
cap nails with a nominal cap diameter of not less than 1 inch (25 mm). Metal
caps shall have a thickness of not less than 32-gage sheet metal. Power-driven
metal caps shall have a thickness of not less than 0.010 inch ( 0.25 mm).
Minimum thickness of the outside edge of plastic caps shall be 0.035 inch (
0.89 mm).
3.4.
The cap nail shank shall be not less than 0.083 inch (
2.11 mm) for ring shank cap nails and 0.091 inch ( 2.31 mm) for smooth shank
cap nails. Cap nail shank shall have a length sufficient to penetrate through
the roof sheathing or not less than3/4 inch (19 mm)
into the roof sheathing.
TABLE 905.1.1(1)
UNDERLAYMENT TYPES
|
ROOF COVERING
|
SECTION
|
MAXIMUM ULTIMATE DESIGN WIND
SPEED, Vult < 140 MPH
|
MAXIMUM ULTIMATE DESIGN WIND
SPEED, Vult >=140 MPH
|
|
Asphalt shingles
|
905.2
|
ASTM D226 Type I
ASTM D4869 Type I, II, III or
IV
ASTM D6757
|
ASTM D226 Type II
ASTM D4869 Type III or Type
IV
ASTM D6757
|
|
Clay and concrete tile
|
905.3
|
ASTM D226 Type II
ASTM D2626 Type I
ASTM D6380 Class M mineral-surfaced
roll roofing
|
ASTM D226 Type II
ASTM D2626 Type I
ASTM D6380 Class M mineral-surfaced
roll roofing
|
|
Metal roof shingles
|
905.4
|
ASTM D226 Type I or II
ASTM D4869 Type I, II, III or
IV
|
ASTM D226 Type II
ASTM D4869 Type III or Type
IV
|
|
Mineral-surfaced roll
roofing
|
905.5
|
ASTM D226 Type I or II
ASTM D4869 Type I, II, III or
IV
|
ASTM D226 Type II
ASTM D4869 Type III or Type
IV
|
|
Slate and slate-type
shingles
|
905.6
|
ASTM D226 Type I
ASTM D4869 Type I, II, III or
IV
|
ASTM D226 Type II
ASTM D4869 Type III or Type
IV
|
|
Wood shingles
|
905.7
|
ASTM D226 Type I or II
ASTM D4869 Type I, II, III or
IV
|
ASTM D226 Type II
ASTM D4869 Type III or Type
IV
|
|
Wood shakes
|
905.8
|
ASTM D226 Type I or II
ASTM D4869 Type I, II, III or
IV
|
ASTM D226 Type II
ASTM D4869 Type III or Type
IV
|
|
Metal panels
|
905.10
|
Manufacturer's
instructions
|
ASTM D226 Type II
ASTM D4869 Type III or Type
IV
|
|
Photovoltaic shingles
|
905.16
|
ASTM D4869 Type I, II, III or
IV
ASTM D6757
|
ASTM D4869 Type III or Type IV
ASTM D6757
|
For SI: 1 mile per hour = 0.447
m/s.
TABLE R05.1.1(2)
UNDERLAYMENT
APPLICATION
|
ROOF COVERING
|
SECTION
|
MAXIMUM ULTIMATE DESIGN WIND
SPEED, Vult < 140 MPH
|
MAXIMUM ULTIMATE DESIGN WIND
SPEED, Vult >=140 MPH
|
|
Asphalt shingles
|
905.2
|
For roof slopes from two units vertical
in 12 units horizontal (2:12), up to four units vertical in 12 units horizontal
(4:12), underlayment shall be two layers applied in the following manner: apply
a 19-inch strip of underlayment felt parallel to and starting at the eaves.
Starting at the eave, apply 36-inch-wide sheets of underlayment, overlapping
successive sheets 19 inches. Distortions in the underlayment shall not
interfere with the ability of the shingles to seal. End laps shall be 4 inches
and shall be offset by 6 feet. For roof slopes of four units vertical in 12
units horizontal (4:12) or greater, underlayment shall be one layer applied in
the following manner: underlayment shall be applied shingle fashion, parallel
to and starting from the eave and lapped 2 inches, Distortions in the
underlayment shall not interfere with the ability of the shingles to seal. End
laps shall be 4 inches and shall be offset by 6 feet.
|
Same as Maximum Ultimate Design Wind
Speed, Vult < 140 mph except all laps shall be not less than 4
inches.
|
|
Clay and concrete tile
|
905.3
|
For roof slopes from two and one-half
units vertical in 12 units horizontal (21/2 :12), up
to four units vertical in 12 units horizontal (4:12), underlayment shall be not
fewer than two layers applied as follows: starting at the eave, apply a 19-inch
strip of underlayment parallel with the eave. Starting at the eave, apply
36-inch-wide strips of underlayment felt, overlapping successive sheets 19
inches. End laps shall be 4 inches and shall be off-set by 6 feet. For roof
slopes of four units vertical in 12 units horizontal (4:12) or greater,
underlayment shall be not fewer than one layer of underlayment felt applied
shingle fashion, parallel to and starting from the eaves and lapped 2 inches.
End laps shall be 4 inches and shall be offset by 6 feet.
|
Same as Maximum Ultimate Design Wind
Speed, Vult < 140 mph, except all laps shall be not less than 4
inches.
|
|
Metal roof shingles
|
905.4
|
Apply in accordance with the
manufacturer's installation instructions.
|
For roof slopes from two units vertical
in 12 units horizontal (2:12), up to four units vertical in 12 units horizontal
(4:12), underlayment shall be two layers applied in the following manner: apply
a 19-inch strip of underlayment felt parallel to and starting at the eaves.
Starting at the eave, apply 36-inch-wide sheets of underlayment, overlapping
successive sheets 19 inches. End laps shall be 4 inches and shall be offset by
6 feet. For roof slopes of four units vertical in 12 units horizontal (4:12) or
greater, underlayment shall be one layer applied in the following manner:
under- layment shall be applied shingle fashion, parallel to and starting from
the eave and lapped 4 inches. End laps shall be 4 inches and shall be offset by
6 feet.
|
|
Mineral-surfaced roll
roofing
|
905.5
|
|
Slate and slate-type
shingles
|
905.6
|
|
Wood shingles
|
905.7
|
|
Wood shakes
|
905.8
|
|
Metal panels
|
905.10
|
|
Photovoltaic shingles
|
905.16
|
For roof slopes from two units vertical
in 12 units horizontal (2:12), up to four units vertical in 12 units horizontal
(4:12), underlayment shall be two layers applied in the following manner: apply
a 19- inch strip of underlayment felt parallel to and starting at the eaves.
Starting at the eave, apply 36-inch- wide sheets of underlayment, overlapping
successive sheets 19 inches. Distortions in the underlayment shall not
interfere with the ability of the shingles to seal. End laps shall be 4 inches
and shall be offset by 6 feet. For roof slopes of four units vertical in 12
units horizontal (4:12) or greater, underlayment shall be one layer applied in
the following manner: underlayment shall be applied shingle fashion, parallel
to and starting from the eave and lapped 2 inches. Distortions in the
underlayment shall not interfere with the ability of the shingles to seal. End
laps shall be 4 inches and shall be offset by 6 feet.
|
Same as Maximum Ultimate Design Wind
Speed, Vult < 140 mph, except all laps shall be not less than 4
inches.
|
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1
mile per hour = 0.447 m/s.
TABLE 905.1.1(3)
UNDERLAYMENT
ATTACHMENT
|
ROOF COVERING
|
SECTION
|
MAXIMUM ULTIMATE DESIGN WIND
SPEED,Vult < 140 MPH
|
MAXIMUM ULTIMATE DESIGN WIND
SPEED, Vult > 140 MPH
|
|
Asphalt shingles
|
905.2
|
Fastened sufficiently to hold in
place
|
The underlayment shall be attached with
corrosion-resistant fasteners in a grid pattern of 12 inches between side laps
with a 6-inch spacing at side and end laps.
Underlayment shall be attached using
metal or plastic cap nails or cap staples with a nominal cap diameter of not
less than 1 inch. Metal caps shall have a thickness of not less than 32-gage
sheet metal. Power-driven metal caps shall have a minimum thickness of 0.010
inch. Minimum thickness of the outside edge of plastic caps shall be 0.035
inch. The cap nail shank shall be not less than 0.083 inch for ring shank cap
nails and 0.091 inch for smooth shank cap nails. Staples shall be not less than
21 gage. Cap nail shank and cap staple legs shall have a length sufficient to
penetrate through the roof sheathing or not less
than3/ inch into the roof sheathing.
|
|
Clay and concrete tile
|
905.3
|
|
Photovoltaic
|
905.16
|
|
Metal roof shingles
|
905.4
|
Manufacturer's installation
instructions.
|
The underlayment shall be attached with
corrosion-resistant fasteners in a grid pattern of 12 inches between side laps
with a 6-inch spacing at side and end laps.
Underlayment shall be attached using
metal or plastic cap nails or cap staples with a nominal cap diameter of not
less than 1 inch. Metal caps shall have a thickness of not less than 32-gage
sheet metal. Power-driven metal caps shall have a minimum thickness of 0.010
inch. Minimum thickness of the outside edge of plastic caps shall be 0.035
inch. The cap nail shank shall be not less than 0.083 inch for ring shank cap
nails and 0.091 inch for smooth shank cap nails. Staples shall be not less than
21 gage. Cap nail shank and cap staple legs shall have a length sufficient to
penetrate through the roof sheathing or not less
than3/ inch into the roof sheathing.
|
|
Mineral-surfaced roll
roofing
|
905.5
|
|
Slate and slate-type
shingles
|
905.6
|
|
Wood shingles
|
905.7
|
|
Wood shakes
|
905.8
|
|
Metal panels
|
905.10
|
For SI: 1 inch = 25.4 mm, 1 mile per hour =
0.447 m/s.
905.1.2
Ice
barriers.
In areas where there has been a
history of ice forming along the eaves causing a backup of water as designated
in Table 301.2(1), an ice barrier shall be installed for asphalt shingles,
metal roof shingles, mineral-surfaced roll roofing, slate and slate-type
shingles, wood shingles and wood shakes. The ice barrier shall consist of not
fewer than two layers of underlayment cemented together, or a self-adhering
polymer-modified bitumen sheet shall be used in place of normal underlayment
and extend from the lowest edges of all roof surfaces to a point not less than
24 inches (610 mm) inside the exterior wall line of the building. The
24 inch measurement shall be along the slope of the roof from the point where
the projected outside face of the wall intersects the roof deck. On
roofs with slope equal to or greater than eight units vertical in 12 units
horizontal (67-percent slope), the ice barrier shall also be applied not less
than 36 inches (914 mm) measured along the roof slope from the eave edge of the
building.
Exception:
Detached accessory structures and roof
assemblies terminating at a vertical wall over unconditioned floor
areas.
905.2
Asphalt
shingles.
The installation of asphalt
shingles shall comply with the provisions of this section.
905.2.1
Sheathing requirements.
Asphalt shingles
shall be fastened to solidly sheathed decks.
905.2.2
Slope.
Asphalt shingles
shall be used only on roof slopes of two units vertical in 12 units horizontal
(17-percent slope) or greater. For roof slopes from two units vertical in 12
units horizontal (17-percent slope) up to four units vertical in 12 units
horizontal (33-percent slope), double underlayment application is required in
accordance with Section 905.1.1.
905.2.3
Underlayment.
Underlayment shall comply
with Section 905.1.1.
905.2.4
Asphalt shingles.
Asphalt shingles shall comply with ASTM D3462.
905.2.4.1
Wind
resistance of asphalt shingles.
Asphalt
shingles shall be tested in accordance with ASTM D7158. Asphalt shingles shall
meet the classification requirements of Table 905.2.4.1 for the appropriate
ultimate design wind speed. Asphalt shingle packaging shall bear a label to
indicate compliance with ASTM D7158 and the required classification in Table
905.2.4.1.
Exception: Asphalt shingles not
included in the scope of ASTM D7158 shall be tested and labeled in accordance
with ASTM D3161. Asphalt shingle packaging shall bear a label to indicate
compliance with ASTM D3161 and the required classification in Table
905.2.4.1.
TABLE 905.2.4.1
CLASSIFICATION OF ASPHALT ROOF
SHINGLES
|
MAXIMUM ULTIMATE DESIGN WIND
SPEED, Vult FROM FIGURE 301.2(5) A (mph)
|
MAXIMUM BASIC WIND SPEED, Vasd
FROM TABLE 301.2.1.3 (mph)
|
ASTM
D7158a SHINGLE CLASSIFICATION
|
ASTM D3161 SHINGLE
CLASSIFICATION
|
|
110
|
85
|
D, G or H
|
A, D or F
|
|
116
|
90
|
D, G or H
|
A, D or F
|
|
129
|
100
|
G or H
|
A, D or F
|
|
142
|
110
|
G or H
|
F
|
|
155
|
120
|
G or H
|
F
|
|
168
|
130
|
H
|
F
|
|
181
|
140
|
H
|
F
|
|
194
|
150
|
H
|
F
|
For SI: 1 foot = 304.8 mm; 1 mile per hour =
0.447 m/s.
a. The standard calculations contained in ASTM
D7158 assume Exposure Category B or C and a building height of 60 feet or less.
Additional calculations are required for conditions outside of these
assumptions.
905.2.5
Fasteners.
Fasteners
for asphalt shingles shall be galvanized steel, stainless steel, aluminum or
copper roofing nails, minimum 12-gage [ 0.105 inch (3 mm)] shank with a
minimum3/8-inch-diameter ( 9.5 mm) head, complying
with ASTM F1667, of a length to penetrate through the roofing materials and not
less than3/4 inch ( 19.1 mm) into the roof
sheathing. Where the roof sheathing is less than3/4
inch ( 19.1 mm) thick, the fasteners shall penetrate through the
sheathing.
905.2.6
Attachment.
Asphalt
shingles shall have the minimum number of fasteners required by the
manufacturer's approved installation instructions, but not less than four
fasteners per strip shingle or two fasteners per individual shingle. Where the
roof slope exceeds 21 units vertical in 12 units horizontal (21:12, 175-percent
slope), shingles shall be installed in accordance with the manufacturer's
approved installation instructions.
905.2.7
Ice
barrier.
Where required, ice barriers
shall comply with Section 905.1.2.
905.2.8
Flashing.
Flashing for
asphalt shingles shall comply with this section and the asphalt shingle
manufacturer's approved installation instructions.
905.2.8.1
Base
and cap flashing.
Base and cap flashing
shall be installed in accordance with manufacturer's instructions. Base
flashing shall be of either corrosion-resistant metal of minimum nominal 0.019
-inch ( 0.5 mm) thickness or mineral-surfaced roll roofing weighing not less
than 77 pounds per 100 square feet (4 kg/m2). Cap
flashing shall be corrosion-resistant metal of minimum nominal 0.019 -inch (
0.5 mm) thickness.
905.2.8.2
Valleys.
Valley linings shall be installed in accordance with the
manufacturer's instructions before applying shingles. Valley linings of the
following types shall be permitted:
1.
For open valleys (valley lining exposed) lined with
metal, the valley lining shall be not less than 24 inches (610 mm) wide and of
any of the corrosion-resistant metals in Table 905.2.8.2.
2.
For open valleys,
valley lining of two plies of mineral-surfaced roll roofing, complying with
ASTM D3909 or ASTM D6380 Class M, shall be permitted. The bottom layer shall be
18 inches (457 mm) and the top layer not less than 36 inches (914 mm)
wide.
3.
For closed valleys (valley covered with shingles),
valley lining of one ply of smooth roll roofing complying with ASTM D6380 and
not less than 36 inches wide (914 mm) or valley lining as described in Item 1
or 2 shall be permitted. Self-adhering polymer-modified bitumen underlayment
complying with ASTM D1970 shall be permitted in lieu of the lining
material.
TABLE 905.2.8.2
VALLEY LINING
MATERIAL
|
MATERIAL
|
MINIMUM THICKNESS
(inches)
|
GAGE
|
WEIGHT
(pounds)
|
|
Cold-rolled copper
|
0.0216 nominal
|
-
|
ASTM B370, 16 oz. per square
foot
|
|
Lead-coated copper
|
0.0216 nominal
|
-
|
ASTM B101, 16 oz. per square
foot
|
|
High-yield copper
|
0.0162 nominal
|
-
|
ASTM B370, 12 oz. per square
foot
|
|
Lead-coated high-yield
copper
|
0.0162 nominal
|
-
|
ASTM B101, 12 oz. per square
foot
|
|
Aluminum
|
0.024
|
-
|
-
|
|
Stainless steel
|
-
|
28
|
-
|
|
Galvanized steel
|
0.0179
|
26 (zinc coated G90)
|
-
|
|
Zinc alloy
|
0.027
|
-
|
-
|
|
Lead
|
-
|
-
|
21/2
|
|
Painted terne
|
-
|
-
|
20
|
For SI: 1 inch = 25.4 mm, 1 pound = 0.454
kg.
905.2.8.3
Sidewall flashing.
Base
flashing against a vertical sidewall shall be continuous or step flashing and
shall be not less than 4 inches (102 mm) in height and 4 inches (102 mm) in
width and shall direct water away from the vertical sidewall onto the roof or
into the gutter. Where siding is provided on the vertical sidewall, the
vertical leg of the flashing shall be continuous under the siding. Where
anchored masonry veneer is provided on the vertical sidewall, the base flashing
shall be provided in accordance with this section and counterflashing shall be
provided in accordance with Section 703.8.2.2. Where exterior plaster or
adhered masonry veneer is provided on the vertical sidewall, the base flashing
shall be provided in accordance with this section and Section
703.6.3.
905.2.8.4
Other flashing.
Flashing against a vertical front wall, as well as soil
stack, vent pipe and chimney flashing, shall be applied in accordance with the
asphalt shingle manufacturer's printed instructions.
905.2.8.5
Drip
edge.
Refer to Sections 903.1 and
905.1.
905.3
Clay and
concrete tile.
The installation of clay
and concrete tile shall comply with the provisions of this section.
905.3.1
Deck
requirements.
Concrete and clay tile shall
be installed only over solid sheathing or spaced structural sheathing
boards.
905.3.2
Deck slope.
Clay and
concrete roof tile shall be installed on roof slopes of two and one-half units
vertical in 12 units horizontal (25-percent slope) or greater. For roof slopes
from two and one-half units vertical in 12 units horizontal (25-percent slope)
to four units vertical in 12 units horizontal (33-percent slope), double
underlayment application is required in accordance with Section
905.3.3.
905.3.3
Underlayment.
Underlayment shall comply with Section
905.1.1.
905.3.4
Clay tile.
Clay roof
tile shall comply with ASTM C1167.
905.3.5
Concrete tile.
Concrete
roof tile shall comply with ASTM C1492.
905.3.6
Fasteners.
Nails shall
be corrosion resistant and not less than 11-gage,
5/16-inch (11 mm) head, and of sufficient length
to penetrate the deck not less than3/4 inch (19 mm)
or through the thickness of the deck, whichever is less. Attaching wire for
clay or concrete tile shall not be smaller than 0.083 inch (2 mm). Perimeter
fastening areas include three tile courses but not less than 36 inches (914 mm)
from either side of hips or ridges and edges of eaves and gable
rakes.
905.3.7
Application.
Tile shall
be applied in accordance with this chapter and the manufacturer's installation
instructions, based on the following:
1.
Climatic conditions.
2.
Roof
slope.
3.
Underlayment system.
4.
Type of tile being
installed.
Clay and concrete roof tiles shall be fastened
in accordance with this section and the manufacturer's installation
instructions. Perimeter tiles shall be fastened with not less than one fastener
per tile. Tiles with installed weight less than 9 pounds per square foot ( 0.4
kg/m2) require not less than one fastener per tile
regardless of roof slope. Clay and concrete roof tile attachment shall be in
accordance with the manufacturer's installation instructions where applied in
areas where the ultimate design wind speed exceeds 130 miles per hour (58 m/s)
and on buildings where the roof is located more than 40 feet (12 192 mm) above
grade. In areas subject to snow, not less than two fasteners per tile are
required. In other areas, clay and concrete roof tiles shall be attached in
accordance with Table 905.3.7.
TABLE 905.3.7
CLAY AND CONCRETE TILE
ATTACHMENT
|
SHEATHING
|
ROOF SLOPE
|
NUMBER OF
FASTENERS
|
|
Solid without battens
|
All
|
One per tile
|
|
Spaced or solid with battens and slope
< 5:12
|
Fasteners not required
|
-
|
|
Spaced sheathing without
battens
|
5:12 < slope < 12:12
|
One per tile/ every other
row
|
|
|
12:12 < slope <
24:12
|
One per tile
|
905.3.8
Flashing.
At the
juncture of roof vertical surfaces, flashing and counterflashing shall be
provided in accordance with this chapter and the manufacturer's installation
instructions and, where of metal, shall be not less than 0.019 inch ( 0.5 mm)
(No. 26 galvanized sheet gage) corrosion-resistant metal. The valley flashing
shall extend not less than 11 inches (279 mm) from the centerline each way and
have a splash diverter rib not less than 1 inch (25 mm) in height at the flow
line formed as part of the flashing. Sections of flashing shall have an end lap
of not less than 4 inches (102 mm). For roof slopes of three units vertical in
12 units horizontal (25-percent slope) and greater, valley flashing shall have
a 36-inch-wide (914 mm) underlayment of one layer of Type I underlayment
running the full length of the valley, in addition to other required
underlayment. In areas where the average daily temperature in January is
25°F (-4°C) or less, metal valley flashing underlayment shall be
solid-cemented to the roofing underlayment for slopes less than seven units
vertical in 12 units horizontal (58-percent slope) or be of self-adhering
polymer-modified bitumen sheet.
905.4
Metal
roof shingles.
The installation of metal
roof shingles shall comply with the provisions of this section.
905.4.1
Deck
requirements.
Metal roof shingles shall be
applied to a solid or closely fitted deck, except where the roof covering is
specifically designed to be applied to spaced sheathing.
905.4.2
Deck
slope.
Metal roof shingles shall not be
installed on roof slopes below three units vertical in 12 units horizontal
(25-percent slope).
905.4.3
Underlayment.
Underlayment shall comply with Section 905.1.1.
905.4.3.1
Ice
barrier.
Where required, ice barriers
shall comply with Section 905.1.2.
905.4.4
Material standards.
Metal roof shingle roof coverings shall comply with Table
905.10.3(1). The materials used for metal roof shingle roof coverings shall be
naturally corrosion resistant or be made corrosion resistant in accordance with
the standards and minimum thicknesses listed in Table
905.10.3(2).
905.4.5
Application.
Metal roof shingles shall be secured to the roof in
accordance with this chapter and the approved manufacturer's installation
instructions.
905.4.6
Flashing.
Roof valley flashing shall be of corrosion-resistant metal
of the same material as the roof covering or shall comply with the standards in
Table 905.10.3(1). The valley flashing shall extend not less than 8 inches (203
mm) from the centerline each way and shall have a splash diverter rib not less
than3/4 inch (19 mm) in height at the flow line
formed as part of the flashing. Sections of flashing shall have an end lap of
not less than 4 inches (102 mm). The metal valley flashing shall have a
36-inch-wide (914 mm) underlayment directly under it consisting of one layer of
underlayment running the full length of the valley, in addition to underlayment
required for metal roof shingles. In areas where the average daily temperature
in January is 25°F (-4°C) or less, the metal valley flashing
underlayment shall be solid-cemented to the roofing underlayment for roof
slopes under seven units vertical in 12 units horizontal (58-percent slope) or
self-adhering polymer-modified bitumen sheet.
905.5
Mineral-surfaced roll roofing.
The installation of mineral-surfaced roll roofing shall
comply with this section.
905.5.1
Deck requirements.
Mineral-surfaced roll roofing shall be fastened to
solidly sheathed roofs.
905.5.2
Deck
slope.
Mineral-surfaced roll roofing shall
not be applied on roof slopes below one unit vertical in 12 units horizontal
(8-percent slope).
905.5.3
Underlayment.
Underlayment shall comply with Section 905.1.1.
905.5.3.1
Ice
barrier.
Where required, ice barriers
shall comply with Section 905.1.2.
905.5.4
Material standards.
Mineral-surfaced roll
roofing shall conform to ASTM D3909 or ASTM D6380, Class M.
905.5.5
Application.
Mineral-surfaced roll roofing shall be installed in
accordance with this chapter and the manufacturer's
instructions.
905.6
Slate
shingles.
The installation of slate
shingles shall comply with the provisions of this section.
905.6.1
Deck
requirements.
Slate shingles shall be
fastened to solidly sheathed roofs.
905.6.2
Deck
slope.
Slate shingles shall be used only
on slopes of four units vertical in 12 units horizontal (33-percent slope) or
greater.
905.6.3
Underlayment.
Underlayment shall comply with Section 905.1.1.
905.6.3.1
Ice
barrier.
Where required, ice barriers
shall comply with Section 905.1.2.
905.6.4
Material standards.
Slate shingles shall comply with ASTM C406.
905.6.5
Application.
Minimum
headlap for slate shingles shall be in accordance with Table 905.6.5. Slate
shingles shall be secured to the roof with two fasteners per slate. Slate
shingles shall be installed in accordance with this chapter and the
manufacturer's instructions.
TABLE 905.6.5
SLATE SHINGLE HEADLAP
|
SLOPE
|
HEADLAP
(inches)
|
|
4:12 <= slope < 8:12
|
4
|
|
8:12 <= slope <
20:12
|
3
|
|
Slope >= 20:12
|
2
|
For SI: 1 inch = 25.4 mm.
905.6.6
Flashing.
Flashing and
counterflashing shall be made with sheet metal. Valley flashing shall be not
less than 15 inches (381 mm) wide. Valley and flashing metal shall be a minimum
uncoated thickness of 0.0179 -inch ( 0.5 mm) zinc coated G90. Chimneys, stucco
or brick walls shall have not less than two plies of felt for a cap flashing
consisting of a 4-inch-wide (102 mm) strip of felt set in plastic cement and
extending 1 inch (25 mm) above the first felt and a top coating of plastic
cement. The felt shall extend 2 inches (51 mm) over the base
flashing.
905.7
Wood shingles.
The installation of wood shingles shall comply with the
provisions of this section.
905.7.1
Deck requirements.
Wood shingles shall be installed on solid or spaced
sheathing. Where spaced sheathing is used, sheathing boards shall be not less
than 1-inch by 4-inch (25 mm by 102 mm) nominal dimensions and shall be spaced
on centers equal to the weather exposure to coincide with the placement of
fasteners.
905.7.1.1
Solid sheathing required.
In areas where the average daily temperature in January
is 25°F (-4°C) or less, solid sheathing is required on that portion of
the roof requiring the application of an ice barrier.
905.7.2
Deck slope.
Wood
shingles shall be installed on slopes of three units vertical in 12 units
horizontal (25-percent slope) or greater.
905.7.3
Underlayment.
Underlayment shall comply with Section 905.1.1.
905.7.3.1
Ice
barrier.
Where required, ice barriers
shall comply with Section 905.1.2.
905.7.4
Material standards.
Wood shingles shall be of naturally durable wood and comply
with the requirements of Table 905.7.4.
TABLE 905.7.4
WOOD SHINGLE MATERIAL
REQUIREMENTS
|
MATERIAL
|
MINIMUM
GRADES
|
APPLICABLE GRADING
RULES
|
|
Wood shingles of naturally durable
wood
|
1, 2 or 3
|
Cedar Shake and Shingle Bureau
(
CSSB)
|
905.7.5
Application.
Wood shingles shall be installed in accordance with this
chapter and the manufacturer's instructions. Wood shingles shall be laid with a
side lap not less than 11/2 inches (38 mm) between
joints in courses, and two joints shall not be in direct alignment in any three
adjacent courses. Spacing between shingles shall be not less
than1/4 inch to3/8 inch (
6.4 mm to 9.5 mm). Weather exposure for wood shingles shall not exceed those
set in Table 905.7.5(1). Fasteners for untreated (naturally durable) wood
shingles shall be box nails in accordance with Table 905.7.5(2). Nails shall be
stainless steel Type 304 or 316 or hot-dipped galvanized with a coating weight
of ASTM A153 Class D ( 1.0 oz/ft2). Alternatively,
two 16-gage stainless steel Type 304 or 316 staples with crown
widths7/16 inch ( 11.1 mm)
minimum,3/4 inch ( 19.1 mm) maximum, shall be used.
Fasteners installed within 15 miles (24 km) of saltwater coastal areas shall be
stainless steel Type 316. Fasteners for fire-retardant-treated shingles in
accordance with Section 902 or pressure-impregnated-preservative-treated
shingles of naturally durable wood in accordance with AWPA U1 shall be
stainless steel Type 316. Fasteners shall have a minimum penetration into the
sheathing of3/4 inch ( 19.1 mm). For sheathing less
than3/4 inch in ( 19.1 mm) thickness, each fastener
shall penetrate through the sheathing. Wood shingles shall be attached to the
roof with two fasteners per shingle, positioned in accordance with the
manufacturer's installation instructions. Fastener packaging shall bear a label
indicating the appropriate grade material or coating weight.
TABLE 905.7.5(1)
WOOD SHINGLE WEATHER EXPOSURE AND ROOF
SLOPE
|
ROOFING
MATERIAL
|
LENGTH
(inches)
|
GRADE
|
EXPOSURE
(inches)
|
|
3:12 pitch to <
4:12
|
4:12 pitch or
steeper
|
|
Shingles of naturally durable
wood
|
16
|
No. 1
|
33/4
|
5
|
|
No. 2
|
31/2
|
4
|
|
No. 3
|
3
|
31/2
|
|
18
|
No. 1
|
41/4
|
51/2
|
|
|
|
No. 2
|
4
|
41/2
|
|
No. 3
|
31/2
|
4
|
|
24
|
No. 1
|
53/4
|
71/2
|
|
No. 2
|
51/2
|
61/2
|
|
No. 3
|
5
|
51/2
|
For SI: 1 inch = 25.4 mm.
TABLE 905.7.5(2)
NAIL REQUIREMENTS FOR WOOD SHAKES AND
WOOD SHINGLES
|
SHAKES
|
NAIL TYPE AND MINIMUM
LENGTH
|
MINIMUM HEAD
SIZE
|
MINIMUM SHANK
DIAMETER
|
|
18" straight-split
|
5d box
13/4"
|
0.19 "
|
.080"
|
|
18" and 24" handsplit and
resawn
|
6d box 2"
|
0.19 "
|
.0915"
|
|
24" taper-split
|
5d box
13/4"
|
0.19 "
|
.080"
|
|
18" and 24" tapersawn
|
6d box 2"
|
0.19 "
|
.0915"
|
|
Shingles
|
Nail Type and Minimum
Length
|
Minimum Head
Size
|
Minimum Shank
Diameter
|
|
16" and 18"
|
3d box
11/4"
|
0.19 "
|
.080"
|
|
24"
|
4d box
11/2"
|
0.19 "
|
.080"
|
For SI: 1 inch = 25.4 mm.
905.7.6
Valley flashing.
Roof
flashing shall be not less than No. 26 gage [ 0.019 inches ( 0.5 mm)]
corrosion-resistant sheet metal and shall extend 10 inches (254 mm) from the
centerline each way for roofs having slopes less than 12 units vertical in 12
units horizontal (100-percent slope), and 7 inches (178 mm) from the centerline
each way for slopes of 12 units vertical in 12 units horizontal (100-percent
slope) and greater. Sections of flashing shall have an end lap of not less than
4 inches (102 mm).
905.7.7
Label required.
Each bundle of shingles shall be identified by a label
of an approved grading or inspection bureau or agency.
905.8
Wood shakes.
The
installation of wood shakes shall comply with the provisions of this
section.
905.8.1
Deck
requirements.
Wood shakes shall be used
only on solid or spaced sheathing. Where spaced sheathing is used, sheathing
boards shall be not less than 1-inch by 4-inch (25 mm by 102 mm) nominal
dimensions and shall be spaced on centers equal to the weather exposure to
coincide with the placement of fasteners. Where 1-inch by 4-inch (25 mm by 102
mm) spaced sheathing is installed at 10 inches (254 mm) on center, additional
1-inch by 4-inch (25 mm by 102 mm) boards shall be installed between the
sheathing boards.
905.8.1.1
Solid sheathing required.
In areas where the average daily temperature in January
is 25°F (-4°C) or less, solid sheathing is required on that portion of
the roof requiring an ice barrier.
905.8.2
Deck
slope.
Wood shakes shall only be used on
slopes of three units vertical in 12 units horizontal (25-percent slope) or
greater.
905.8.3
Underlayment.
Underlayment shall comply with Section 905.1.1.
905.8.3.1
Ice
barrier.
Where required, ice barriers
shall comply with Section 905.1.2.
905.8.4
Interlayment.
Interlayment shall comply with ASTM D226, Type
I.
905.8.5
Material standards.
Wood shakes shall comply with the requirements of Table
905.8.5.
TABLE 905.8.5
WOOD SHAKE MATERIAL
REQUIREMENTS
|
MATERIAL
|
MINIMUM
GRADES
|
APPLICABLE GRADING
RULES
|
|
Wood shakes of naturally durable
wood
|
1
|
Cedar Shake and Shingle
Bureau
|
|
Tapersawn shakes of naturally durable
wood
|
1 or 2
|
Cedar Shake and Shingle
Bureau
|
|
Preservative-treated shakes and
shingles of naturally durable wood
|
1
|
Cedar Shake and Shingle
Bureau
|
|
Fire-retardant-treated shakes and
shingles of naturally durable wood
|
1
|
Cedar Shake and Shingle
Bureau
|
|
Preservative-treated tapersawn shakes
of Southern pine treated in accordance with AWPA Standard U1 (Commodity
Specification A, Special Requirement 4.6)
|
1or 2
|
Forest Products Laboratory of the Texas
Forest Services
|
905.8.6
Application.
Wood shakes shall be installed in accordance with this
chapter and the manufacturer's installation instructions. Wood shakes shall be
laid with a side lap not less than 11/2 inches (38
mm) between joints in adjacent courses. Spacing between shakes in the same
course shall be3/8 inch
to5/8 inch ( 9.5 mm to 15.9 mm) including tapersawn
shakes. Weather exposures for wood shakes shall not exceed those set in Table
905.8.6. Fasteners for untreated (naturally durable) wood shakes shall be box
nails in accordance with Table 905.7.5(2). Nails shall be stainless steel Type
304, or Type 316 or hot-dipped with a coating weight of ASTM A153 Class D ( 1.0
oz/ft2). Alternatively, two 16-gage Type 304 or Type
316 stainless steel staples, with crown widths7/16
inch ( 11.1 mm) minimum,3/4 inch ( 19.1 mm) maximum,
shall be used. Fasteners installed within 15 miles (24 km) of saltwater coastal
areas shall be stainless steel Type 316. Wood shakes shall be attached to the
roof with two fasteners per shake positioned in accordance with the
manufacturer's installation instructions Fasteners for fire-retardant-treated
(as defined in Section 902) shakes or pressure-impregnated-preservative-treated
shakes of naturally durable wood in accordance with AWPA U1 shall be stainless
steel Type 316. Fasteners shall have a minimum penetration into the sheathing
of3/4 inch ( 19.1 mm). Where the sheathing is less
than3/4 inch ( 19.1 mm) thick, each fastener shall
penetrate through the sheathing. Fastener packaging shall bear a label
indicating the appropriate grade material or coating weight.
TABLE 905.8.6
WOOD SHAKE WEATHER EXPOSURE AND ROOF
SLOPE
|
ROOFING
MATERIAL
|
LENGTH
(inches)
|
GRADE
|
EXPOSURE
(inches)
|
|
4:12 pitch or
steeper
|
|
Shakes of naturally durable
wood
|
18
|
No. 1
|
71/2
|
|
24
|
No. 1
|
10a
|
|
Preservative-treated tapersawn shakes
of Southern Yellow Pine
|
18
|
No. 1
|
71/2
|
|
24
|
No. 1
|
10
|
|
18
|
No. 2
|
51/2
|
|
24
|
No. 2
|
71/2
|
|
Taper-sawn shakes of naturally durable
wood
|
18
|
No. 1
|
71/2
|
|
24
|
No. 1
|
10
|
|
18
|
No. 2
|
51/2
|
|
24
|
No. 2
|
71/2
|
For SI: 1 inch = 25.4 mm.
a. For 24-inch
by3/8-inch handsplit shakes, the maximum exposure is
71/2 inches.
905.8.7
Shake
placement.
The starter course at the eaves
shall be doubled and the bottom layer shall be either 15-inch (381 mm), 18-inch
(457 mm) or 24-inch (610 mm) wood shakes or wood shingles. Fifteen-inch (381
mm) or 18-inch (457 mm) wood shakes shall be permitted to be used for the final
course at the ridge. Shakes shall be interlaid with 18-inch-wide (457 mm)
strips of not less than No. 30 felt shingled between each course in such a
manner that felt is not exposed to the weather by positioning the lower edge of
each felt strip above the butt end of the shake it covers a distance equal to
twice the weather exposure.
905.8.8
Valley
flashing.
Roof valley flashing shall be
not less than No. 26 gage [ 0.019 inch ( 0.5 mm)] corrosion-resistant sheet
metal and shall extend not less than 11 inches (279 mm) from the centerline
each way. Sections of flashing shall have an end lap of not less than 4 inches
(102 mm).
905.8.9
Label required.
Each
bundle of shakes shall be identified by a label of an approved grading or
inspection bureau or agency.
905.9
Built-up
roofs.
The installation of built-up roofs
shall comply with the provisions of this section and the manufacturer's
approved installation instructions.
905.9.1
Slope.
Built-up roofs shall have a design slope
of not less than one-fourth unit vertical in 12 units horizontal (2-percent
slope) for drainage, except for coal-tar built-up roofs, which shall have a
design slope of a minimum one-eighth unit vertical in 12 units horizontal
(1-percent slope).
905.9.2
Material standards.
Built-up roof covering materials shall comply with the
standards in Table 905.9.2 or UL 55A.
TABLE 905.9.2
BUILT-UP ROOFING MATERIAL
STANDARDS
|
MATERIAL
STANDARD
|
STANDARD
|
|
Acrylic coatings used in
roofing
|
ASTM D6083
|
|
Aggregate surfacing
|
ASTM D1863
|
|
Asphalt adhesive used in
roofing
|
ASTM D3747
|
|
Asphalt cements used in
roofing
|
ASTM D2822; D3019; D4586
|
|
Asphalt-coated glass fiber base
sheet
|
ASTM D4601
|
|
Asphalt coatings used in
roofing
|
ASTM D1227; D2823; D2824;
D4479
|
|
Asphalt glass felt
|
ASTM D2178
|
|
Asphalt primer used in
roofing
|
ASTM D41
|
|
Asphalt-saturated and asphalt-coated
organic felt base sheet
|
ASTM D2626
|
|
Asphalt-saturated organic felt
(perforated)
|
ASTM D226
|
|
Asphalt used in roofing
|
ASTM D312
|
|
Coal-tar cements used in
roofing
|
ASTM D4022; D5643
|
|
Coal-tar primer used in roofing,
dampproofing and waterproofing
|
ASTM D43
|
|
Coal-tar saturated organic
felt
|
ASTM D227
|
|
Coal-tar used in roofing
|
ASTM D450, Type I or II
|
|
Glass mat, coal tar
|
ASTM D4990
|
|
Glass mat, venting type
|
ASTM D4897
|
|
Mineral-surfaced inorganic cap
sheet
|
ASTM D3909
|
|
Thermoplastic fabrics used in
roofing
|
ASTM D5665; D5726
|
905.9.3
Application.
Built-up roofs shall be installed in accordance with this
chapter and the manufacturer's instructions.
905.10
Metal
roof panels.
The installation of metal
roof panels shall comply with the provisions of this section.
905.10.1
Deck
requirements.
Metal roof panel roof
coverings shall be applied to solid or spaced sheathing, except where the roof
covering is specifically designed to be applied to spaced
supports.
905.10.2
Slope.
Minimum slopes
for metal roof panels shall comply with the following:
1.
The minimum slope
for lapped, nonsoldered-seam metal roofs without applied lap sealant shall be
three units vertical in 12 units horizontal (25-percent slope).
2.
The minimum slope
for lapped, nonsoldered-seam metal roofs with applied lap sealant shall be
one-half unit vertical in 12 units horizontal (4-percent slope). Lap sealants
shall be applied in accordance with the approved manufacturer's installation
instructions.
3.
The minimum slope for standing-seam roof systems shall
be one-quarter unit vertical in 12 units horizontal (2-percent
slope).
905.10.3
Material standards.
Metal-sheet roof covering systems that incorporate
supporting structural members shall be designed in accordance with the
Ohio building code. Metal-sheet roof coverings installed over
structural decking shall comply with Table 905.10.3(1). The materials used for
metal-sheet roof coverings shall be naturally corrosion resistant or provided
with corrosion resistance in accordance with the standards and minimum
thicknesses shown in Table 905.10.3(2).
TABLE 905.10.3(1)
METAL ROOF COVERING
STANDARDS
|
ROOF COVERING
TYPE
|
STANDARD APPLICATION
RATE/THICKNESS
|
|
Galvanized steel
|
ASTM A653 G90 Zinc coated
|
|
Stainless steel
|
ASTM A240, 300 Series
alloys
|
|
Steel
|
ASTM A924
|
|
Lead-coated copper
|
ASTM B101
|
|
Cold-rolled copper
|
ASTM B370 minimum 16 oz/sq ft and 12
oz/sq ft high-yield copper for metal-sheet roof-covering systems; 12 oz/sq ft
for preformed metal shingle systems.
|
|
Hard lead
|
2 lb/sq ft
|
|
Soft lead
|
3 lb/sq ft
|
|
Aluminum
|
ASTM B209, 0.024 minimum thickness for
roll-formed panels and 0.019 -inch minimum thickness for pressformed
shingles.
|
|
Terne (tin) and terne-coated
stainless
|
Terne coating of 40 lb per double base
box, field painted where applicable in accordance with manufacturer's
installation instructions.
|
|
Zinc
|
0.027 inch minimum thickness: 99.995 %
electrolytic high-grade zinc with alloy additives of copper ( 0.08 - 0.20 %),
titanium ( 0.07 % - 0.12 %) and aluminum ( 0.015 %).
|
For SI: 1 ounce per square foot = 0.305
kg/m2, 1 pound per square foot = 4.214
kg/m2, 1 inch = 25.4 mm, 1 pound = 0.454
kg.
TABLE 905.10.3(2)
MINIMUM CORROSION
RESISTANCE
|
55% aluminum-zinc-alloy-coated
steel
|
ASTM A792 AZ 50
|
|
5% aluminum alloy-coated
steel
|
ASTM A875 GF60
|
|
Aluminum-coated steel
|
ASTM A463 T2 65
|
|
Galvanized steel
|
ASTM A653 G-90
|
|
Prepainted steel
|
ASTM
A755a
|
a. Paint systems in accordance with ASTM A755
shall be applied over steel products with corrosion-resistant coatings
complying with ASTM A792, ASTM A875, ASTM A463, or ASTM A653.
905.10.4
Attachment.
Metal roof
panels shall be secured to the supports in accordance with this chapter and the
manufacturer's installation instructions. In the absence of manufacturer's
installation instructions, the following fasteners shall be used:
1.
Galvanized
fasteners shall be used for steel roofs.
2.
Copper, brass,
bronze, copper alloy and 300-series stainless steel fasteners shall be used for
copper roofs.
3.
Stainless steel fasteners are acceptable for metal
roofs.
905.10.5
Underlayment.
Underlayment shall comply with Section
905.1.1.
905.11
Modified bitumen roofing.
The installation of modified bitumen roofing shall
comply with the provisions of this section and the manufacturer's approved
installation instructions.
905.11.1
Slope.
Modified bitumen roofing shall have a design slope of not
less than one-fourth unit vertical in 12 units horizontal (2-percent slope) for
drainage.
905.11.2
Material standards.
Modified bitumen roofing shall comply with the standards in
Table 905.11.2.
TABLE 905.11.2
MODIFIED BITUMEN ROOFING MATERIAL
STANDARDS
|
MATERIAL
|
STANDARD
|
|
Acrylic coating
|
ASTM D6083
|
|
Asphalt adhesive
|
ASTM D3747
|
|
Asphalt cement
|
ASTM D3019
|
|
Asphalt coating
|
ASTM D1227; D2824
|
|
Asphalt primer
|
ASTM D41
|
|
Modified bitumen roof
membrane
|
ASTM D6162; D6163; D6164; D6222; D6223;
D6298
|
905.11.2.1
Base sheet.
A base
sheet that complies with the requirements of Section 1507.11.2 of the
Ohio building code, ASTM D1970, or ASTM D4601 shall be
permitted to be used with a modified bitumen cap sheet.
905.11.3
Application.
Modified
bitumen roofs shall be installed in accordance with this chapter and the
manufacturer's instructions.
905.12
Thermoset single-ply roofing.
The installation of thermoset single-ply roofing shall
comply with the provisions of this section.
905.12.1
Slope.
Thermoset
single-ply membrane roofs shall have a design slope of not less than one-fourth
unit vertical in 12 units horizontal (2-percent slope) for
drainage.
905.12.2
Material standards.
Thermoset single-ply roof coverings shall comply with ASTM
D4637 or ASTM D5019.
905.12.3
Application.
Thermoset single-ply roofs shall be installed in accordance
with this chapter and the manufacturer's instructions.
905.13
Thermoplastic single-ply roofing.
The installation of thermoplastic single-ply roofing
shall comply with the provisions of this section.
905.13.1
Slope.
Thermoplastic
single-ply membrane roofs shall have a design slope of not less than one-fourth
unit vertical in 12 units horizontal (2-percent slope).
905.13.2
Material standards.
Thermoplastic single-ply roof coverings shall comply with
ASTM D4434, ASTM D6754 or ASTM D6878.
905.13.3
Application.
Thermoplastic single-ply roofs shall be installed in
accordance with this chapter and the manufacturer's
instructions.
905.14
Sprayed
polyurethane foam roofing.
The
installation of sprayed polyurethane foam roofing shall comply with the
provisions of this section.
905.14.1
Slope.
Sprayed polyurethane foam roofs shall have a design slope of
not less than one-fourth unit vertical in 12 units horizontal (2-percent slope)
for drainage.
905.14.2
Material standards.
Spray-applied polyurethane foam insulation shall comply
with ASTM C1029, Type III or IV or ASTM D7425.
905.14.3
Application.
Foamed-in-place roof insulation shall be installed in
accordance with this chapter and the manufacturer's instructions. A
liquid-applied protective coating that complies with Table 905.14.3 shall be
applied not less than 2 hours nor more than 72 hours following the application
of the foam.
TABLE 905.14.3
PROTECTIVE COATING MATERIAL
STANDARDS
|
MATERIAL
|
STANDARD
|
|
Acrylic coating
|
ASTM D6083
|
|
Silicone coating
|
ASTM D6694
|
|
Moisture-cured polyurethane
coating
|
ASTM D6947
|
905.14.4
Foam plastics.
Foam plastic materials and installation shall comply
with Section 316.
905.15
Liquid-applied roofing.
The installation of liquid-applied roofing shall comply with
the provisions of this section.
905.15.1
Slope.
Liquid-applied
roofing shall have a design slope of not less than one-fourth unit vertical in
12 units horizontal (2-percent slope).
905.15.2
Material standards.
Liquid-applied roofing shall comply with ASTM C836, C957,
D1227, D3468, D6083, D6694 or D6947.
905.15.3
Application.
Liquid-applied roofing shall be installed in accordance with
this chapter and the manufacturer's installation instructions.
905.16
Photovoltaic shingles.
The installation of photovoltaic shingles shall comply with
the provisions of this section, Section 324 and NFPA 70.
905.16.1
Deck
requirements.
Photovoltaic shingles shall
be applied to a solid or closely-fitted deck, except where the roof covering is
specifically designed to be applied over spaced sheathing.
905.16.2
Deck
slope.
Photovoltaic shingles shall be used
only on roof slopes of two units vertical in 12 units horizontal (2:12) or
greater.
905.16.3
Underlayment.
Underlayment shall comply with Section 905.1.1.
905.16.3.1
Ice
barrier.
Where required, ice barriers
shall comply with Section 905.1.2.
905.16.4
Material standards.
Photovoltaic shingles shall be listed and labeled in
accordance with UL 1703.
905.16.5
Attachment.
Photovoltaic shingles shall be attached in accordance with
the manufacturer's installation instructions.
905.16.6
Wind
resistance.
Photovoltaic shingles shall be
tested in accordance with procedures and acceptance criteria in ASTM D3161.
Photovoltaic shingles shall comply with the classification requirements of
Table 905.2.4.1 for the appropriate maximum basic wind speed. Photovoltaic
shingle packaging shall bear a label to indicate compliance with the procedures
in ASTM D3161 and the required classification from Table
905.2.4.1.
905.17
Building-integrated Photovoltaic (BIPV) roof
panels applied directly to the roof deck.
The installation of BIPV roof panels shall comply with the
provisions of this section, Section 324 and NFPA 70.
905.17.1
Deck
requirements.
BIPV roof panels shall be
applied to a solid or closely-fitted deck, except where the roof covering is
specifically designed to be applied over spaced sheathing.
905.17.2
Deck
slope.
BIPV roof panels shall be used only
on roof slopes of two units vertical in 12 units horizontal (17-percent slope)
or greater.
905.17.3
Underlayment.
Underlayment shall comply with Section 905.1.1.
905.17.3.1
Ice
barrier.
Where required, an ice barrier
shall comply with Section 905.1.2.
905.17.4
Ice
barrier.
In areas where there has been a
history of ice forming along the eaves causing a backup of water, as designated
in Table 301.2(1), an ice barrier that consists of not less than two layers of
underlayment cemented together or of a self-adhering polymer-modified bitumen
sheet shall be used in lieu of normal underlayment and extend from the lowest
edges of all roof surfaces to a point not less than 24 inches (610 mm) inside
the exterior wall line of the building.
Exception:
Detached accessory structures that do not contain
conditioned floor area.
905.17.5
Material standards.
BIPV roof panels shall be listed and labeled in accordance
with UL 1703.
905.17.6
Attachment.
BIPV roof panels shall be attached in accordance with the
manufacturer's installation instructions.
905.17.7
Wind
resistance.
BIPV roof panels shall be
tested in accordance with UL 1897. BIPV roof panel packaging shall bear a label
to indicate compliance with UL 1897.
SECTION 908
REROOFING
908.1
General.
Materials and methods of application used
for re-covering or replacing an existing roof covering shall comply with the
requirements of Chapter 9.
Exceptions:
1.
Reroofing shall
not be required to meet the minimum design slope requirement of one-quarter
unit vertical in 12 units horizontal (2-percent slope) in Section 905 for roofs
that provide positive roof drainage.
2.
For roofs that
provide positive drainage, re-covering or replacing an existing roof covering
shall not require the secondary (emergency overflow) drains or scuppers of
Section 903.4.1 to be added to an existing roof.
908.2
Structural and construction loads.
The structural roof components shall be capable of
supporting the roof covering system and the material and equipment loads that
will be encountered during installation of the roof covering
system.
908.3
Roof replacement.
Roof
replacement shall include the removal of existing layers of roof coverings down
to the roof deck.
Exception:
Where the existing roof assembly includes an ice
barrier membrane that is adhered to the roof deck, the existing ice barrier
membrane shall be permitted to remain in place and covered with an additional
layer of ice barrier membrane in accordance with Section 905.
908.3.1
Roof
recover.
The installation of a new roof
covering over an existing roof covering shall be permitted where any of the
following conditions occur:
1.
Where the new roof covering is installed in accordance
with the roof covering manufacturer's approved instructions
2.
Complete and
separate roofing systems, such as standing-seam metal roof systems, that are
designed to transmit the roof loads directly to the building's structural
system and do not rely on existing roofs and roof coverings for support, shall
not require the removal of existing roof coverings.
3.
Metal panel, metal
shingle and concrete and clay tile roof coverings shall be permitted to be
installed over existing wood shake roofs where applied in accordance with
Section 908.4.
4.
The application of a new protective roof coating over
an existing protective roof coating, metal roof panel, metal roof shingle,
mineral surfaced roll roofing, built-up roof, modified bitumen roofing,
thermoset and thermoplastic single-ply roofing and spray polyurethane foam
roofing system shall be permitted without tear-off of existing roof
coverings.
908.3.1.1
Roof recover not allowed.
A roof recover shall not be permitted where any of the
following conditions occur:
1.
Where the existing roof or roof covering is water
soaked or has deteriorated to the point that the existing roof or roof covering
is not adequate as a base for additional roofing.
2.
Where the existing
roof covering is slate, clay, cement or asbestos-cement tile.
3.
Where the existing
roof has two or more applications of any type of roof covering.
908.4
Roof recovering.
Where the application of a new roof covering over wood
shingle or shake roofs creates a combustible concealed space, the entire
existing surface shall be covered with gypsum board, mineral fiber, glass fiber
or other approved materials securely fastened in place.
908.5
Reinstallation of materials.
Existing slate, clay or cement tile shall be permitted
for reinstallation, except that damaged, cracked or broken slate or tile shall
not be reinstalled. Any existing flashings, edgings, outlets, vents or similar
devices that are a part of the assembly shall be replaced where rusted, damaged
or deteriorated. Aggregate surfacing materials shall not be
reinstalled.
908.6
Flashings.
Flashings
shall be reconstructed in accordance with approved manufacturer's installation
instructions. Metal flashing to which bituminous materials are to be adhered
shall be primed prior to installation.
Replaces: 4101:8-9-01
