User note: Code change proposals to sections preceded by the designation [BF], [BG] or [P] will be considered by one of the code development committees meeting during the 2015 (Group A) Code Development Cycle. All other code change proposals will be considered by the IBC — Structural Code Development Committee during the 2016 (Group B) Code Development Cycle. See explanation on page iv.
The provisions of this chapter shall govern the
design, materials, construction and quality of roof assemblies,
and rooftop structures.
The following terms are defined in Chapter 2:
AGGREGATE.
BALLAST.
BUILDING-INTEGRATED PHOTOVOLTAIC (BIPV) PRODUCT.
BUILT-UP ROOF COVERING.
INTERLAYMENT.
MECHANICAL EQUIPMENT SCREEN.
METAL ROOF PANEL.
METAL ROOF SHINGLE.
MODIFIED BITUMEN ROOF COVERING.
PENTHOUSE.
PHOTOVOLTAIC MODULE.
PHOTOVOLTAIC PANEL.
PHOTOVOLTAIC PANEL SYSTEM.
PHOTOVOLTAIC SHINGLES.
POSITIVE ROOF DRAINAGE.
RADIANT BARRIER.
REROOFING.
ROOF ASSEMBLY.
ROOF COVERING.
ROOF COVERING SYSTEM.
ROOF DECK.
ROOF RECOVER.
ROOF REPAIR.
ROOF REPLACEMENT.
ROOF VENTILATION.
ROOFTOP STRUCTURE.
SCUPPER.
SINGLE-PLY MEMBRANE.
UNDERLAYMENT.
VEGETATIVE ROOF.
AGGREGATE.
BALLAST.
BUILDING-INTEGRATED PHOTOVOLTAIC (BIPV) PRODUCT.
BUILT-UP ROOF COVERING.
INTERLAYMENT.
MECHANICAL EQUIPMENT SCREEN.
METAL ROOF PANEL.
METAL ROOF SHINGLE.
MODIFIED BITUMEN ROOF COVERING.
PENTHOUSE.
PHOTOVOLTAIC MODULE.
PHOTOVOLTAIC PANEL.
PHOTOVOLTAIC PANEL SYSTEM.
PHOTOVOLTAIC SHINGLES.
POSITIVE ROOF DRAINAGE.
RADIANT BARRIER.
REROOFING.
ROOF ASSEMBLY.
ROOF COVERING.
ROOF COVERING SYSTEM.
ROOF DECK.
ROOF RECOVER.
ROOF REPAIR.
ROOF REPLACEMENT.
ROOF VENTILATION.
ROOFTOP STRUCTURE.
SCUPPER.
SINGLE-PLY MEMBRANE.
UNDERLAYMENT.
VEGETATIVE ROOF.
Upcodes Diagrams
Roof decks shall be covered with approved roof coverings secured to the building or structure in accordance with the provisions of this chapter. Roof coverings shall be designed and installed in accordance with this code and the approved manufacturer's instructions such that the roof covering shall serve to protect the building or structure.
Flashing shall be installed in such a manner
so as to prevent moisture entering the wall and roof through
joints in copings, through moisture-permeable materials and
at intersections with parapet walls and other penetrations
through the roof plane.
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Flashing shall be installed at wall and
roof intersections, at gutters, wherever there is a change in
roof slope or direction and around roof openings. Where
flashing is of metal, the metal shall be corrosion resistant
with a thickness of not less than 0.019 inch (0.483 mm)
(No. 26 galvanized sheet).
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Parapet walls shall be properly coped with
noncombustible, weatherproof materials of a width no less
than the thickness of the parapet wall.
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Design and installation of roof
drainage systems shall comply with Section 1503 of this code
and Sections 1106 and 1108, as applicable, of the International
Plumbing Code.
Where roof drains are required, secondary
(emergency overflow) roof drains or scuppers shall be provided
where the roof perimeter construction extends above
the roof in such a manner that water will be entrapped if
the primary drains allow buildup for any reason. The
installation and sizing of secondary emergency overflow
drains, leaders and conductors shall comply with Sections
1106 and 1108, as applicable, of the International Plumbing
Code.
When scuppers are used for secondary (emergency overflow) roof drainage, the quantity, size, location and inlet elevation of the scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by Section 1611.1. Scuppers shall not have an opening dimension of less than 4 inches (102 mm). The flow through the primary system shall not be considered when locating and sizing scuppers.
Gutters and leaders placed on the outside
of buildings, other than Group R-3, private garages
and buildings of Type V construction, shall be of noncombustible material or a minimum of Schedule 40 plastic
pipe.
Intake and exhaust
vents shall be provided in accordance with Section 1203.2
and the vent product manufacturer's installation instructions.
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A cricket or saddle shall be
installed on the ridge side of any chimney or penetration
greater than 30 inches (762 mm) wide as measured perpendicular
to the slope. Cricket or saddle coverings shall be sheet
metal or of the same material as the roof covering.
Exception:
Unit skylights installed in accordance with
Section 2405.5 and flashed in accordance with the manufacturer's
instructions shall be permitted to be installed
without a cricket or saddle.
Upcodes Diagrams
Roof decks and roof coverings
shall be designed for wind loads in accordance with
Chapter 16 and Sections 1504.2, 1504.3 and 1504.4.
Asphalt shingles shall be tested in accordance with ASTM D7158. Asphalt shingles shall meet the classification requirements of Table 1504.1.1 for the appropriate maximum basic wind speed. Asphalt shingle packaging shall bear a label to indicate compliance with ASTM D7158 and the required classification in Table 1504.1.1.
For SI: 1 foot = 304.8 mm; 1 mph = 0.447 m/s.
Exception: Asphalt shingles that are not included in the scope of ASTM D7158 shall be tested and labeled to indicate compliance with ASTM D3161 and the required classification in Table 1504.1.1.
MAXIMUM BASIC WIND SPEED, Vult, FROM FIGURE 1609.3(1), 1609.3(2), 1609.3(3) OR ASCE 7 | MAXIMUM BASIC WIND SPEED, Vasd, FROM TABLE 1609.3.1 | ASTM D7158a CLASSIFICATION | ASTM D3161 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 |
- The standard calculations contained in ASTM D7158 assume Exposure Category B or C and building height of 60 feet or less. Additional calculations are required for conditions outside of these assumptions.
Upcodes Diagrams
Testing of concrete and clay roof tiles
shall be in accordance with Sections 1504.2.1.1 and
1504.2.1.2.
Concrete and clay roof tiles shall be tested to determine their resistance to overturning due to wind in accordance with SBCCI SSTD 11 and Chapter 15.
Where concrete and
clay roof tiles do not satisfy the limitations in Chapter
16 for rigid tile, a wind tunnel test shall be used to
determine the wind characteristics of the concrete or
clay tile roof covering in accordance with SBCCI
SSTD 11 and Chapter 15.
Roof coverings
installed on roofs in accordance with Section 1507 that
are mechanically attached or adhered to the roof deck shall be
designed to resist the design wind load pressures for components
and cladding in accordance with Section 1609.
Where
the metal roof panel functions as the roof deck and roof
covering and it provides both weather protection and support
for loads, the structural metal panel roof system shall
comply with this section. Structural standing-seam metal panel roof systems shall be tested in accordance with
ASTM E1592 or FM 4474. Structural through-fastened
metal panel roof systems shall be tested in accordance
with FM 4474, UL 580 or ASTM E1592.
Exceptions:
- Metal roofs constructed of cold-formed steel shall be permitted to be designed and tested in accordance with the applicable referenced structural design standard in Section 2210.1.
- Metal roofs constructed of aluminum shall be permitted to be designed and tested in accordance with the applicable referenced structural design standard in Section 2002.1.
Ballasted low-slope (roof slope < 2:12) single-ply roof system coverings installed in accordance with Sections 1507.12 and 1507.13 shall be designed in accordance with Section 1504.8 and ANSI/SPRI RP-4.
Low-slope built-up, modified bitumen and single-ply roof system metal edge securement, except gutters, shall be designed and installed for wind loads in accordance with Chapter 16 and tested for resistance in accordance with Test Methods RE-1, RE-2 and RE-3 of ANSI/SPRI ES-1, except Vult wind speed shall be determined from Figure 1609.3(1), 1609.3(2) or 1609.3(3) as applicable.
Roof coverings installed on
low-slope roofs (roof slope < 2:12) in accordance with Section
1507 shall demonstrate physical integrity over the working
life of the roof based upon 2,000 hours of exposure to
accelerated weathering tests conducted in accordance with
ASTM G152, ASTM G155 or ASTM G154. Those roof coverings
that are subject to cyclical flexural response due to
wind loads shall not demonstrate any significant loss of tensile
strength for unreinforced membranes or breaking
strength for reinforced membranes when tested as herein
required.
Roof coverings installed on low-slope
roofs (roof slope < 2:12) in accordance with Section
1507 shall resist impact damage based on the results of tests
conducted in accordance with ASTM D3746, ASTM D4272,
CGSB 37-GP-52M or the "Resistance to Foot Traffic Test" in
Section 5.5 of FM 4470.
Aggregate used as surfacing for roof coverings and aggregate, gravel or stone used as ballast shall not be used on the roof of a building located in a hurricane-prone region as defined in Section 202, or on any other building with a mean roof height exceeding that permitted by Table 1504.8 based on the exposure category and basic wind speed at the site.
For SI: 1 foot = 304.8 mm; 1 mile per hour = 0.447 m/s.
NOMINAL DESIGN WIND SPEED, Vasd (mph)b, d | MAXIMUM MEAN ROOF HEIGHT (ft)a, c | ||
---|---|---|---|
Exposure category | |||
B | C | D | |
85 | 170 | 60 | 30 |
90 | 110 | 35 | 15 |
95 | 75 | 20 | NP |
100 | 55 | 15 | NP |
105 | 40 | NP | NP |
110 | 30 | NP | NP |
115 | 20 | NP | NP |
120 | 15 | NP | NP |
Greater than 120 | NP | NP | NP |
- Mean roof height as defined in ASCE 7.
- For intermediate values of Vasd, the height associated with the next higher value of Vasd shall be used, or direct interpolation is permitted.
- NP = gravel and stone not permitted for any roof height.
- Vasd shall be determined in accordance with Section 1609.3.1.
Roof assemblies shall be divided into the classes defined below. Class A, B and C roof assemblies and roof coverings required to be listed by this section shall be tested in accordance with ASTM E108 or UL 790. In addition, fire-retardant-treated wood roof coverings shall be tested in accordance with ASTM D2898. The minimum roof coverings installed on buildings shall comply with Table 1505.1 based on the type of construction of the building.
For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929 m2.
IA | IB | IIA | IIB | IIIA | IIIB | IV | VA | VB |
B | B | B | Cc | B | Cc | B | B | Cc |
- Unless otherwise required in accordance with the International Wildland-Urban Interface Code or due to the location of the building within a fire district in accordance with Appendix D.
- Nonclassified roof coverings shall be permitted on buildings of Group R-3 and Group U occupancies, where there is a minimum fire-separation distance of 6 feet measured from the leading edge of the roof.
- Buildings that are not more than two stories above grade plane and having not more than 6,000 square feet of projected roof area and where there is a minimum 10-foot fire-separation distance from the leading edge of the roof to a lot line on all sides of the building, except for street fronts or public ways, shall be permitted to have roofs of No. 1 cedar or redwood shakes and No. 1 shingles constructed in accordance with Section 1505.7.
Upcodes Diagrams
Class A roof assemblies
are those that are effective against severe fire test exposure.
Class A roof assemblies and roof coverings shall be
listed and identified as Class A by an approved testing
agency. Class A roof assemblies shall be permitted for use in
buildings or structures of all types of construction.
Exceptions:
- Class A roof assemblies include those with coverings of brick, masonry or an exposed concrete roof deck.
- Class A roof assemblies also include ferrous or copper shingles or sheets, metal sheets and shingles, clay or concrete roof tile or slate installed on noncombustible decks or ferrous, copper or metal sheets installed without a roof deck on noncombustible framing.
- Class A roof assemblies include minimum 16 ounce per square foot (0.0416 kg/m2) copper sheets installed over combustible decks.
- Class A roof assemblies include slate installed over ASTM D226, Type II underlayment over combustible decks.
Class B roof assemblies
are those that are effective against moderate fire-test
exposure. Class B roof assemblies and roof coverings shall be
listed and identified as Class B by an approved testing
agency.
Class C roof assemblies
are those that are effective against light fire-test exposure.
Class C roof assemblies and roof coverings shall be
listed and identified as Class C by an approved testing
agency.
Upcodes Diagrams
Nonclassified roofing is
approved material that is not listed as a Class A, B or C roof
covering.
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 also be labeled to identify
the classification of the material in accordance with the
testing required in Section 1505.1, the treating company and
the quality control agency.
Special purpose wood
shingle or wood shake roofing shall conform to the grading
and application requirements of Section 1507.8 or 1507.9. In
addition, an underlayment of 5/8-inch (15.9 mm) Type X
water-resistant gypsum backing board or gypsum sheathing
shall be placed under minimum nominal 1/2-inch-thick (12.7
mm) wood structural panel solid sheathing or 1-inch (25 mm)
nominal spaced sheathing.
Building-integrated photovoltaic products installed as the
roof covering shall be tested, listed and labeled for fire classification
in accordance with Section 1505.1.
Rooftop-mounted
photovoltaic panel systems shall be tested, listed and
identified with a fire classification in accordance with UL
1703. The fire classification shall comply with Table 1505.1
based on the type of construction of the building.
Roof
gardens and landscaped roofs shall comply with Section
1507.16 and shall be installed in accordance with ANSI/SPRI
VF-1.
Upcodes Diagrams
The requirements set forth in this section shall
apply to the application of roof-covering materials specified
herein. Roof coverings shall be applied in accordance with
this chapter and the manufacturer's installation instructions.
Installation of roof coverings shall comply with the applicable
provisions of Section 1507.
Roof-covering materials shall conform to the applicable
standards listed in this chapter.
Roof-covering materials
shall be delivered in packages bearing the manufacturer's
identifying marks and approved testing agency labels
required in accordance with Section 1505. Bulk shipments of
materials shall be accompanied with the same information
issued in the form of a certificate or on a bill of lading by the
manufacturer.
Roof coverings shall be applied in accordance
with the applicable provisions of this section and the manufacturer's
installation instructions.
The installation of asphalt shingles
shall comply with the provisions of this section.
Upcodes Diagrams
Asphalt shingles shall be
fastened to solidly sheathed decks.
Asphalt shingles shall only be used 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 1507.2.8.
Unless otherwise noted,
required underlayment shall conform to ASTM D226,
Type I, ASTM D4869, Type I, or ASTM D6757.
Self-adhering polymer modified bitumen sheet shall
comply with ASTM D1970.
Asphalt shingles shall comply
with ASTM D225 or ASTM D3462.
Fasteners for asphalt shingles shall be
galvanized, stainless steel, aluminum or copper roofing
nails, minimum 12-gage [0.105 inch (2.67 mm)] shank
with a minimum 3/8-inch-diameter (9.5 mm) head, of a
length to penetrate through the roofing materials and a
minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Where the roof sheathing is less than 3/4 inch (19.1 mm)
thick, the nails shall penetrate through the sheathing. Fasteners
shall comply with ASTM F1667.
Upcodes Diagrams
Asphalt shingles shall have the
minimum number of fasteners required by the manufacturer,
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),
shingles shall be installed as required by the manufacturer.
For roof slopes
from two units vertical in 12 units horizontal (17-percent
slope) and up to four units vertical in 12 units horizontal
(33-percent slope), underlayment shall be two layers
applied in the following manner. Apply a minimum 19-inch-wide (483 mm) strip of underlayment felt parallel
with and starting at the eaves, fastened sufficiently to hold
in place. Starting at the eave, apply 36-inch-wide (914
mm) sheets of underlayment overlapping successive
sheets 19 inches (483 mm) and fasten sufficiently to hold
in place. Distortions in the underlayment shall not interfere
with the ability of the shingles to seal. For roof slopes
of four units vertical in 12 units horizontal (33-percent
slope) 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 (51 mm), fastened sufficiently to hold in
place. Distortions in the underlayment shall not interfere
with the ability of the shingles to seal.
Underlayment applied in areas subject to high winds [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's instructions. Fasteners are to be applied along the overlap not more than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall comply with ASTM D226 Type II, ASTM D4869 Type IV, or ASTM D6757. The underlayment shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch (152 mm) spacing at the side laps. Underlayment shall be applied in accordance with Section 1507.2.8 except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception:
As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
In areas where there has been a
history of ice forming along the eaves causing a backup
of water, an ice barrier that consists of at least 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 at least 24 inches (610 mm)
inside the exterior wall line of the building.
Exception:
Detached accessory structures that contain
no conditioned floor area.
Flashing for asphalt shingles shall
comply with this section. Flashing shall be applied in
accordance with this section and the asphalt shingle manufacturer's
printed instructions.
Base and cap flashing
shall be installed in accordance with the manufacturer's
instructions. Base flashing shall be of either
corrosion-resistant metal of minimum nominal 0.019-inch (0.483 mm) thickness or mineral-surfaced roll
roofing weighing a minimum of 77 pounds per 100
square feet (3.76 kg/m2). Cap flashing shall be corrosion-resistant metal of minimum nominal 0.019-inch
(0.483 mm) thickness.
Valley linings shall be installed in accordance with the manufacturer's instructions before applying shingles. Valley linings of the following types shall be permitted:
For SI: 1 inch = 25.4 mm, 1 pound = 0.454 kg, 1 ounce = 28.35 g, 1 square foot = 0.0929 m2.
- For open valleys (valley lining exposed) lined with metal, the valley lining shall be at least 24 inches (610 mm) wide and of any of the corrosion-resistant metals in Table 1507.2.9.2.
- For open valleys, valley lining of two plies of mineral-surfaced roll roofing complying with ASTM D3909 or ASTM D6380 shall be permitted. The bottom layer shall be 18 inches (457 mm) and the top layer a minimum of 36 inches (914 mm) wide.
- For closed valleys (valleys covered with shingles), valley lining of one ply of smooth roll roofing complying with ASTM D6380, and at least 36 inches (914 mm) wide or types as described in Item 1 or 2 above shall be permitted. Self-adhering polymer modified bitumen underlayment complying with ASTM D1970 shall be permitted in lieu of the lining material.
MATERIAL | MINIMUM THICKNESS | GAGE | WEIGHT |
---|---|---|---|
Aluminum
|
0.024 in. | — | — |
Cold-rolled copper
|
0.0216 in. | — | ASTM B370, 16 oz. per square ft. |
Copper
|
— | — | 16 oz |
Galvanized steel
|
0.0179 in. | 26 (zinc-coated G90) | — |
High-yield copper
|
0.0162 in. | — | ASTM B370, 12 oz. per square ft. |
Lead
|
— | — | 2.5 pounds |
Lead-coated copper
|
0.0216 in. | — | ASTM B101, 16 oz. per square ft. |
Lead-coated high-yield copper
|
0.0162 in. | — | ASTM B101, 12 oz. per square ft. |
Painted terne
|
— | — | 20 pounds |
Stainless steel
|
— | 28 | — |
Zinc alloy
|
0.027 in. | — | — |
Upcodes Diagrams
A drip edge shall be provided at eaves and rake edges of shingle roofs. Adjacent segments of the drip edge shall be lapped a minimum of 2 inches (51 mm). The vertical leg of drip edges shall be a minimum of 11/2 inches (38 mm) in width and shall extend a minimum of 1/4 inch (6.4 mm) below sheathing. The drip edge shall extend back on the roof a minimum of 2 inches (51 mm). Underlayment shall be installed over drip edges along eaves. Drip edges shall be installed over underlayment along rake edges. Drip edges shall be mechanically fastened a maximum of 12 inches (305 mm) on center.
The installation of clay and
concrete tile shall comply with the provisions of this section.
Upcodes Diagrams
Clay and concrete roof tile shall be
installed on roof slopes of 21/2 units vertical in 12 units
horizontal (21-percent slope) or greater. For roof slopes
from 21/2 units vertical in 12 units horizontal (21-percent
slope) to four units vertical in 12 units horizontal (33-percent
slope), double underlayment application is required in
accordance with Section 1507.3.3.
Unless otherwise noted,
required underlayment shall conform to: ASTM D226,
Type II; ASTM D2626 or ASTM D6380, Class M mineral-surfaced roll roofing.
For roof slopes from 21/2 units vertical in 12 units horizontal (21-percent slope), up to four units vertical in 12 units horizontal (33-percent slope), underlayment shall be a minimum of two layers applied as follows:
- Starting at the eave, a 19-inch (483 mm) strip of underlayment shall be applied parallel with the eave and fastened sufficiently in place.
- Starting at the eave, 36-inch-wide (914 mm) strips of underlayment felt shall be applied overlapping successive sheets 19 inches (483 mm) and fastened sufficiently in place.
For roof slopes of four
units vertical in 12 units horizontal (33-percent slope)
or greater, underlayment shall be a minimum of one
layer of underlayment felt applied shingle fashion, parallel to, and starting from the eaves and lapped 2 inches
(51 mm), fastened only as necessary to hold in place.
Underlayment applied in areas subject to high wind [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's installation instructions. Fasteners are to be applied along the overlap not more than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch (152 mm) spacing at the side laps. Underlayment shall be applied in accordance with Sections 1507.3.3.1 and 1507.3.3.2 except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception:
As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
Clay roof tile shall comply with ASTM
C1167.
Concrete roof tile shall comply
with ASTM C1492.
Tile fasteners shall be corrosion resistant and not less than 11-gage, 5/16-inch (8.0 mm) head, and of sufficient length to penetrate the deck a minimum of 3/4 inch (19.1 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 (2.1 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.
Clay and concrete roof tiles shall be fastened in accordance with Table 1507.3.7.
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447 m/s, 1 pound per square foot = 4.882 kg/m2.
GENERAL - CLAY OR CONCRETE ROOF TILE | ||||
---|---|---|---|---|
Maximum Nominal Design Wind Speed, Vasd f (mph)
|
Mean roof height
(feet)
|
Roof slope < 3:12
|
Roof slope 3:12 and over
|
|
85
|
0-60
|
One fastener per tile. Flat tile without vertical laps, two fasteners per tile. | Two fasteners per tile. Only one fastener on slopes of 7:12 and less for tiles with installed weight exceeding 7.5 lbs./sq. ft. having a width not more than 16 inches. | |
100
|
0-40
|
|||
100
|
> 40-60
|
The head of all tiles shall be nailed. The nose of all eave tiles shall be fastened with approved clips. All rake tiles shall be nailed with two nails. The nose of all ridge, hip and rake tiles shall be set in a bead of roofer's mastic. | ||
110
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
120
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
130
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
All
|
> 60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
INTERLOCKING CLAY OR CONCRETE ROOF TILE WITH PROJECTING ANCHOR LUGSd, e
(Installations on spaced/solid sheathing with battens or spaced sheathing)
|
||||
Maximum Nominal Design Wind Speed, Vasd f (mph)
|
Mean roof height
(feet)
|
Roof slope < 5:12
|
Roof slope 5:12 < 12:12
|
Roof slope 12:12 and over
|
85
|
0-60
|
Fasteners are not required. Tiles with installed weight less than 9 lbs./sq. ft. require a minimum of one fastener per tile. | One fastener per tile every other row. All perimeter tiles require one fastener. Tiles with installed weight less than 9 lbs./sq. ft. require a minimum of one fastener per tile. | One fastener required for every tile. Tiles with installed weight less than 9 lbs./sq. ft. require a minimum of one fastener per tile. |
100
|
0-40
|
|||
100
|
> 40-60
|
The head of all tiles shall be nailed. The nose of all eave tiles shall be fastened with approved clips. All rake tiles shall be nailed with two nails. The nose of all ridge, hip and rake tiles shall be set in a bead of roofer's mastic. | ||
110
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
120
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
130
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
All
|
> 60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
INTERLOCKING CLAY OR CONCRETE ROOF TILE WITH PROJECTING ANCHOR LUGS
(Installations on solid sheathing without battens)
|
||||
Maximum Nominal Design Wind Speed, Vasd f(mph)
|
Mean roof height
(feet)
|
All roof slopes
|
||
85
|
0-60
|
One fastener per tile. | ||
100
|
0-40
|
One fastener per tile. | ||
100
|
> 40-60
|
The head of all tiles shall be nailed. The nose of all eave tiles shall be fastened with approved clips. All rake tiles shall be nailed with two nails. The nose of all ridge, hip and rake tiles shall be set in a bead of roofer's mastic. | ||
110
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
120
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
130
|
0-60
|
The fastening system shall resist the wind forces in Section 1609.5.3. | ||
All
|
> 60
|
The fastening system shall resist the wind forces in Section 1609.5.3. |
- Minimum fastener size. Corrosion-resistant nails not less than No. 11 gage with 5/16-inch head. Fasteners shall be long enough to penetrate into the sheathing 3/4 inch or through the thickness of the sheathing, whichever is less. Attaching wire for clay and concrete tile shall not be smaller than 0.083 inch.
- Snow areas. A minimum of two fasteners per tile are required or battens and one fastener.
- Roof slopes greater than 24:12. The nose of all tiles shall be securely fastened.
- Horizontal battens. Battens shall be not less than 1 inch by 2 inch nominal. Provisions shall be made for drainage by a minimum of 1/8-inch riser at each nail or by 4-foot-long battens with at least a 1/2-inch separation between battens. Horizontal battens are required for slopes over 7:12.
- Perimeter fastening areas include three tile courses but not less than 36 inches from either side of hips or ridges and edges of eaves and gable rakes.
- Vasd shall be determined in accordance with Section 1609.3.1.
Tile shall be applied according to the manufacturer's installation instructions, based on the following:
- Climatic conditions.
- Roof slope.
- Underlayment system.
- Type of tile being installed.
At the juncture of the roof vertical surfaces,
flashing and counterflashing shall be provided in
accordance with the manufacturer's installation instructions,
and where of metal, shall not be less than 0.019-inch
(0.48 mm) (No. 26 galvanized sheet gage) corrosion-resistant
metal. The valley flashing shall extend at least 11
inches (279 mm) from the centerline each way and have a
splash diverter rib not less than 1 inch (25 mm) high 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 over, the valley flashing
shall have a 36-inch-wide (914 mm) underlayment of
either one layer of Type I underlayment running the full
length of the valley, or a self-adhering polymer-modified
bitumen sheet complying with ASTM D1970, in addition
to other required underlayment. In areas where the average
daily temperature in January is 25°F (-4°C) or less or
where there is a possibility of ice forming along the eaves
causing a backup of water, the metal valley flashing
underlayment shall be solid cemented to the roofing
underlayment for slopes under seven units vertical in 12
units horizontal (58-percent slope) or self-adhering polymer-modified bitumen sheet shall be installed.
Upcodes Diagrams
The installation of metal roof panels
shall comply with the provisions of this section.
Metal roof panel roof coverings
shall be applied to a solid or closely fitted deck,
except where the roof covering is specifically designed to
be applied to spaced supports.
Minimum slopes for metal roof panels
shall comply with the following:
- The minimum slope for lapped, nonsoldered seam metal roof panels without applied lap sealant shall be three units vertical in 12 units horizontal (25-percent slope).
- The minimum slope for lapped, nonsoldered seam metal roof panels 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.
- The minimum slope for standing-seam metal roof panel systems shall be one-quarter unit vertical in 12 units horizontal (2-percent slope).
Metal-sheet roof covering systems that incorporate supporting structural members shall be designed in accordance with Chapter 22. Metal-sheet roof coverings installed over structural decking shall comply with Table 1507.4.3(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 1507.4.3(2).
ROOF COVERING TYPE | STANDARD APPLICATION RATE/THICKNESS |
---|---|
Aluminum | ASTM B209, 0.024 inch minimum thickness for roll-formed panels and 0.019 inch minimum thickness for press-formed shingles. |
Aluminum-zinc alloy coated steel | ASTM A792 AZ 50 |
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. |
Copper | 16 oz./sq. ft. for metal-sheet roof-covering systems; 12 oz./sq. ft. for preformed metal shingle systems. |
Galvanized steel | ASTM A653 G-90 zinc-coateda. |
Hard lead | 2 lbs./sq. ft. |
Lead-coated copper | ASTM B101 |
Prepainted steel | ASTM A755 |
Soft lead | 3 lbs./sq. ft. |
Stainless steel | ASTM A240, 300 Series Alloys |
Steel | ASTM A924 |
Terne and terne-coated stainless | Terne coating of 40 lbs. 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 = 4.882 kg/m2, 1 inch = 25.4 mm, 1 pound = 0.454 kg.
- For Group U buildings, the minimum coating thickness for ASTM A653 galvanized steel roofing shall be G-60.
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 |
- 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.
Metal roof panels shall be secured
to the supports in accordance with the approved manufacturer's
fasteners. In the absence of manufacturer recommendations,
the following fasteners shall be used:
- Galvanized fasteners shall be used for steel roofs.
- Copper, brass, bronze, copper alloy or 300 series stainless-steel fasteners shall be used for copper roofs.
- Stainless-steel fasteners are acceptable for all types of metal roofs.
- Aluminum fasteners are acceptable for aluminum roofs attached to aluminum supports.
Underlayment applied in areas subject to high winds [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's installation instructions. Fasteners are to be applied along the overlap not more than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall comply with ASTM D226 Type II, ASTM D4869 Type IV, or ASTM D1970. The underlayment shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch (152 mm) spacing at the side laps. Underlayment shall be applied in accordance with the manufacturer's installation instructions except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception: As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
The installation of metal roof
shingles shall comply with the provisions of this section.
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.
Metal roof shingles shall not be
installed on roof slopes below three units vertical in 12
units horizontal (25-percent slope).
Underlayment shall comply with ASTM D226, Type I or ASTM D4869.
Underlayment applied in areas subject to high winds [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's installation instructions. Fasteners are to be applied along the overlap not farther apart than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall comply with ASTM D226 Type II or ASTM D4869 Type IV. The underlayment shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch spacing (152 mm) at the side laps. Underlayment shall be applied in accordance with the manufacturer's installation instructions except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception: As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
In areas where there has been a history
of ice forming along the eaves causing a backup of
water, an ice barrier that consists of at least 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 at least 24 inches (610 mm)
inside the exterior wall line of the building.
Exception:
Detached accessory structures that contain
no conditioned floor area.
Metal roof shingle roof
coverings shall comply with Table 1507.4.3(1). The materials
used for metal-roof shingle roof coverings shall be
naturally corrosion resistant or provided with corrosion
resistance in accordance with the standards and minimum
thicknesses specified in the standards listed in Table
1507.4.3(2).
Metal roof shingles shall be
secured to the roof in accordance with the approved manufacturer's
installation instructions.
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
1507.4.3(1). The valley flashing shall extend at least 8
inches (203 mm) from the centerline each way and shall
have a splash diverter rib not less than 3/4 inch (19.1 mm)
high 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). In areas where the average daily temperature
in January is 25°F (-4°C) or less or where there is
a possibility of ice forming along the eaves causing a
backup of water, the metal valley flashing shall have a 36-inch-wide (914 mm) underlayment directly under it consisting
of either one layer of underlayment running the full
length of the valley or a self-adhering polymer-modified
bitumen sheet complying with ASTM D1970, in addition
to underlayment required for metal roof shingles. The
metal valley flashing underlayment shall be solidly
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 shall be installed.
The installation of
mineral-surfaced roll roofing shall comply with this section.
Mineral-surfaced roll roofing
shall be fastened to solidly sheathed roofs.
Mineral-surfaced roll roofing shall
not be applied on roof slopes below one unit vertical in 12
units horizontal (8-percent slope).
Underlayment shall comply with ASTM D226, Type I or ASTM D4869.
Underlayment applied in areas subject to high winds [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's installation instructions. Fasteners are to be applied along the overlap not more than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall comply with ASTM D226 Type II. The underlayment shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch (152 mm) spacing at the side laps. Underlayment shall be applied in accordance with the manufacturer's installation instructions except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception: As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
In areas where there has been a history
of ice forming along the eaves causing a backup of
water, an ice barrier that consists of at least 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 at least 24 inches (610 mm)
inside the exterior wall line of the building.
Exception:
Detached accessory structures that contain
no conditioned floor area.
Mineral-surfaced roll roofing
shall conform to ASTM D3909 or ASTM D6380.
The installation of slate shingles shall
comply with the provisions of this section.
Slate shingles shall be fastened
to solidly sheathed roofs.
Slate shingles shall only be used on
slopes of four units vertical in 12 units horizontal (4:12) or
greater.
Underlayment shall comply
with ASTM D226, Type II or ASTM D4869, Type III or
IV.
Underlayment applied in areas subject to high winds [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's installation instructions. Fasteners are to be applied along the overlap not more than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall comply with ASTM D226, Type II or ASTM D4869, Type IV. The underlayment shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch (152 mm) spacing at the side laps. Underlayment shall be applied in accordance with the manufacturer's installation instructions except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception: As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
In areas where the average daily
temperature in January is 25°F (-4°C) or less or where
there is a possibility of ice forming along the eaves causing
a backup of water, an ice barrier that consists of at
least two layers of underlayment cemented together or of a
self-adhering polymer-modified bitumen sheet shall
extend from the lowest edges of all roof surfaces to a point
at least 24 inches (610 mm) inside the exterior wall line of
the building.
Exception:
Detached accessory structures that contain
no conditioned floor area.
Upcodes Diagrams
Slate shingles shall comply
with ASTM C406.
Minimum headlap for slate shingles shall be in accordance with Table 1507.7.6. Slate shingles shall be secured to the roof with two fasteners per slate.
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.
Flashing and counterflashing shall be
made with sheet metal. Valley flashing shall be a minimum
of 15 inches (381 mm) wide. Valley and flashing
metal shall be a minimum uncoated thickness of 0.0179-inch (0.455 mm) zinc-coated G90. Chimneys, stucco or
brick walls shall have a minimum of 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 over the base flashing 2 inches (51 mm).
The installation of wood shingles shall comply with the provisions of this section and Table 1507.8.
For SI: 1 inch = 25.4 mm, °C = [(°F) - 32]/1.8.
ROOF ITEM | WOOD SHINGLES | WOOD SHAKES |
---|---|---|
1. Roof slope | Wood shingles shall be installed on slopes of not less than three units vertical in 12 units horizontal (3:12). | Wood shakes shall be installed on slopes of not less than four units vertical in 12 units horizontal (4:12). |
2. Deck requirement | ||
Temperate climate | Shingles shall be applied to roofs with solid or spaced sheathing. Where spaced sheathing is used, sheathing boards shall be not less than 1" × 4" nominal dimensions and shall be spaced on centers equal to the weather exposure to coincide with the placement of fasteners. | Shakes shall be applied to roofs with solid or spaced sheathing. Where spaced sheathing is used, sheathing boards shall be not less than 1" × 4" nominal dimensions and shall be spaced on centers equal to the weather exposure to coincide with the placement of fasteners. When 1" × 4" spaced sheathing is installed at 10 inches, boards must be installed between the sheathing boards. |
In areas where the average daily temperature in January is 25°F or less or where there is a possibility of ice forming along the eaves causing a backup of water. | Solid sheathing is required. | Solid sheathing is required. |
3. Interlayment | No requirements. | Interlayment shall comply with ASTM D226, Type 1. |
4. Underlayment | ||
Temperate climate | Underlayment shall comply with ASTM D226, Type 1. | Underlayment shall comply with ASTM D226, Type 1. |
In areas where there is a possibility of ice forming along the eaves causing a backup of water. | An ice barrier that consists of at least two layers of underlayment cemented together or of a self-adhering polymer-modified bitumen sheet shall extend from the eave's edge to a point at least 24 inches inside the exterior wall line of the building. | An ice barrier that consists of at least two layers of underlayment cemented together or of a self-adhering polymer-modified bitumen sheet shall extend from the lowest edges of all roof surfaces to a point at least 24 inches inside the exterior wall line of the building. |
5. Application | ||
Attachment | Fasteners for wood shingles shall be hot-dipped galvanized or Type 304 (Type 316 for coastal areas) stainless steel with a minimum penetration of 0.75 inch into the sheathing. For sheathing less than 0.5 inch thick, the fasteners shall extend through the sheathing. | Fasteners for wood shakes shall be hot-dipped galvanized or Type 304 (Type 316 for coastal areas) with a minimum penetration of 0.75 inch into the sheathing. For sheathing less than 0.5 inch thick, the fasteners shall extend through the sheathing. |
No. of fasteners | Two per shingle. | Two per shake. |
Exposure | Weather exposures shall not exceed those set forth in Table 1507.8.7. | Weather exposures shall not exceed those set forth in Table 1507.9.8. |
Method | Shingles shall be laid with a side lap of not less than 1.5 inches between joints in courses, and no two joints in any three adjacent courses shall be in direct alignment. Spacing between shingles shall be 0.25 to 0.375 inch. | Shakes shall be laid with a side lap of not less than 1.5 inches between joints in adjacent courses. Spacing between shakes shall not be less than 0.375 inch or more than 0.625 inch for shakes and taper sawn shakes of naturally durable wood and shall be 0.25 to 0.375 inch for preservative-treated taper sawn shakes. |
Flashing | In accordance with Section 1507.8.8. | In accordance with Section 1507.9.9. |
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.
Wood shingles shall be installed on
slopes of not less than three units vertical in 12 units horizontal
(25-percent slope).
Underlayment shall comply with ASTM D226, Type I or ASTM D4869.
Underlayment applied in areas subject to high winds [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's installation instructions. Fasteners are to be applied along the overlap not more than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall comply with ASTM D226, Type II or ASTM D4869, Type IV. The underlayment shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch (152 mm) spacing at the side laps. Underlayment shall be applied in accordance with the manufacturer's installation instructions except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception: As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
In areas where there has been a history
of ice forming along the eaves causing a backup of
water, an ice barrier that consists of at least 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 at least 24 inches (610 mm)
inside the exterior wall line of the building.
Exception:
Detached accessory structures that contain
no conditioned floor area.
Wood shingles shall be of naturally durable wood and comply with the requirements of Table 1507.8.5.
CSSB = Cedar Shake and Shingle Bureau
MATERIAL | APPLICABLE MINIMUM GRADES | GRADING RULES |
---|---|---|
Wood shingles of naturally durable wood | 1, 2 or 3 | CSSB |
Fasteners for wood shingles shall be
corrosion resistant with a minimum penetration of 3/4 inch
(19.1 mm) into the sheathing. For sheathing less than 1/2
inch (12.7 mm) in thickness, the fasteners shall extend
through the sheathing. Each shingle shall be attached with
a minimum of two fasteners.
Wood shingles shall be laid with a side lap not less than 11/2 inches (38 mm) between joints in adjacent courses, and not be in direct alignment in alternate courses. Spacing between shingles shall be 1/4 to 3/8 inch (6.4 to 9.5 mm). Weather exposure for wood shingles shall not exceed that set in Table 1507.8.7.
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 | 3.75 | 5 |
No. 2 | 3.5 | 4 | ||
No. 3 | 3 | 3.5 | ||
18 | No. 1 | 4.25 | 5.5 | |
No. 2 | 4 | 4.5 | ||
No. 3 | 3.5 | 4 | ||
24 | No. 1 | 5.75 | 7.5 | |
No. 2 | 5.5 | 6.5 | ||
No. 3 | 5 | 5.5 |
For SI: 1 inch = 25.4 mm.
At the juncture of the roof and vertical surfaces, flashing and counterflashing shall be provided in accordance with the manufacturer's installation instructions, and where of metal, shall be not less than 0.019-inch (0.48 mm) (No. 26 galvanized sheet gage) corrosion-resistant metal. The valley flashing shall extend at least 11 inches (279 mm) from the centerline each way and have a splash diverter rib not less than 1 inch (25 mm) high 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 over, the valley flashing shall have a 36-inch-wide (914 mm) underlayment of either one layer of Type I underlayment running the full length of the valley or a self-adhering polymer-modified bitumen sheet complying with ASTM D1970, in addition to other required underlayment. In areas where the average daily temperature in January is 25°F (-4°C) or less or where there is a possibility of ice forming along the eaves causing a backup of water, the metal valley flashing underlayment shall be solidly cemented to the roofing underlayment for slopes under seven units vertical in 12 units horizontal (58-percent slope) or self-adhering polymer-modified bitumen sheet shall be installed.
The installation of wood shakes shall
comply with the provisions of this section and Table 1507.8.
Wood shakes shall only be
used 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.
Wood shakes shall only be used on
slopes of not less than four units vertical in 12 units horizontal
(33-percent slope).
Underlayment shall comply
with ASTM D226, Type I or ASTM D4869.
Underlayment applied in areas subject to high winds [Vasd greater than 110 mph (49 m/s) as determined in accordance with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's installation instructions. Fasteners are to be applied along the overlap not more than 36 inches (914 mm) on center.
Underlayment installed where Vasd, in accordance with Section 1609.3.1, equals or exceeds 120 mph (54 m/s) shall comply with ASTM D226, Type II or ASTM D4869 Type IV. The underlayment shall be attached in a grid pattern of 12 inches (305 mm) between side laps with a 6-inch (152 mm) spacing at the side laps. Underlayment shall be applied in accordance with the manufacturer's installation instructions except all laps shall be a minimum of 4 inches (102 mm). Underlayment shall be attached using metal or plastic cap nails with a head diameter of not less than 1 inch (25 mm) with a thickness of at least 32-gage [0.0134 inch (0.34 mm)] sheet metal. The cap nail shank shall be a minimum of 12 gage [0.105 inch (2.67 mm)] with a length to penetrate through the roof sheathing or a minimum of 3/4 inch (19.1 mm) into the roof sheathing.
Exception: As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.
In areas where there has been a history
of ice forming along the eaves causing a backup of
water, an ice barrier that consists of at least 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 at least 24 inches (610 mm)
inside the exterior wall line of the building.
Exception:
Detached accessory structures that contain
no conditioned floor area.
Upcodes Diagrams
Interlayment shall comply with ASTM D226, Type I.
Wood shakes shall comply with the requirements of Table 1507.9.6.
CSSB = Cedar Shake and Shingle Bureau.
TFS = Forest Products Laboratory of the Texas Forest Services.
MATERIAL | MINIMUM GRADES | APPLICABLE GRADING RULES |
---|---|---|
Wood shakes of naturally durable wood
|
1 | CSSB |
Taper sawn shakes of naturally durable wood
|
1 or 2 | CSSB |
Preservative-treated shakes and shingles of naturally durable wood
|
1 | CSSB |
Fire-retardant-treated shakes and shingles of naturally durable wood
|
1 | CSSB |
Preservative-treated taper sawn shakes of Southern pine treated in accordance with AWPA U1 (Commodity Specification A, Use Category 3B and Section 5.6)
|
1 or 2 | TFS |
TFS = Forest Products Laboratory of the Texas Forest Services.
Fasteners for wood shakes shall be
corrosion resistant with a minimum penetration of 3/4 inch
(19.1 mm) into the sheathing. For sheathing less than 1/2
inch (12.7 mm) in thickness, the fasteners shall extend
through the sheathing. Each shake shall be attached with a
minimum of two fasteners.
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 be 3/8 to 5/8 inch (9.5 to 15.9 mm) for shakes and taper sawn shakes of naturally durable wood and shall be 1/4 to 3/8 inch (6.4 to 9.5 mm) for preservative taper sawn shakes. Weather exposure for wood shakes shall not exceed those set in Table 1507.9.8.
For SI: 1 inch = 25.4 mm.
ROOFING MATERIAL | LENGTH (inches) | GRADE | EXPOSURE (inches) 4:12 PITCH OR STEEPER |
---|---|---|---|
Shakes of naturally durable wood
|
18 | No. 1 | 7.5 |
24
|
No. 1
|
10a
|
|
Preservative-treated taper sawn shakes of Southern yellow pine
|
18 | No. 1 | 7.5 |
24 | No. 1 | 10 | |
18 | No. 2 | 5.5 | |
24 | No. 2 | 7.5 | |
Taper sawn shakes of naturally durable wood
|
18 | No. 1 | 7.5 |
24 | No. 1 | 10 | |
18 | No. 2 | 5.5 | |
24 | No. 2 | 7.5 |
- For 24-inch by 0.375-inch handsplit shakes, the maximum exposure is 7.5 inches.
At the juncture of the roof and vertical
surfaces, flashing and counterflashing shall be provided in
accordance with the manufacturer's installation instructions,
and where of metal, shall be not less than 0.019-inch
(0.48 mm) (No. 26 galvanized sheet gage) corrosion-resistant
metal. The valley flashing shall extend at least 11
inches (279 mm) from the centerline each way and have a
splash diverter rib not less than 1 inch (25 mm) high 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 over, the valley flashing
shall have a 36-inch-wide (914 mm) underlayment of
either one layer of Type I underlayment running the full
length of the valley or a self-adhering polymer-modified
bitumen sheet complying with ASTM D1970, in addition
to other required underlayment. In areas where the average
daily temperature in January is 25°F (-4°C) or less or
where there is a possibility of ice forming along the eaves
causing a backup of water, the metal valley flashing
underlayment shall be solidly cemented to the roofing
underlayment for slopes under seven units vertical in 12
units horizontal (58-percent slope) or self-adhering polymer-modified bitumen sheet shall be installed.
The installation of built-up roofs
shall comply with the provisions of this section.
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 that shall have a design slope of not less
than one-eighth unit vertical in 12 units horizontal (1-percent
slope).
Built-up roof covering materials shall comply with the standards in Table 1507.10.2 or UL 55A.
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 D3019; D2822; 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 saturated organic felt | ASTM D227 |
Coal-tar pitch used in roofing | ASTM D450; Type I or II |
Coal-tar primer used in roofing, dampproofing and waterproofing | ASTM D43 |
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 |
The installation of modified
bitumen roofing shall comply with the provisions of this
section.
Modified bitumen membrane roofs shall
have a design slope of not less than one-fourth unit vertical
in 12 units horizontal (2-percent slope) for drainage.
Modified bitumen roof
coverings shall comply with CGSB 37-GP-56M, ASTM
D6162, ASTM D6163, ASTM D6164, ASTM D6222,
ASTM D6223, ASTM D6298 or ASTM D6509.
The installation of
thermoset single-ply roofing shall comply with the provisions
of this section.
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.
Thermoset single-ply roof
coverings shall comply with ASTM D4637, ASTM D5019
or CGSB 37-GP-52M.
The installation
of thermoplastic single-ply roofing shall comply with the
provisions of this section.
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).
Thermoplastic single-ply
roof coverings shall comply with ASTM D4434,
ASTM D6754, ASTM D6878 or CGSB CAN/CGSB 37-54.
The installation
of sprayed polyurethane foam roofing shall comply with
the provisions of this section.
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.
Spray-applied polyurethane
foam insulation shall comply with Type III or IV as
defined in ASTM C1029.
Foamed-in-place roof insulation
shall be installed in accordance with the manufacturer's
instructions. A liquid-applied protective coating that complies
with Table 1507.14.3 shall be applied no less than 2
hours nor more than 72 hours following the application of
the foam.
MATERIAL | STANDARD |
---|---|
Acrylic coating | ASTM D6083 |
Silicone coating | ASTM D6694 |
Moisture-cured polyurethane coating | ASTM D6947 |
Foam plastic materials and
installation shall comply with Chapter 26.
The installation of liquid-applied
roofing shall comply with the provisions of this section.
Liquid-applied roofing shall have a
design slope of not less than one-fourth unit vertical in 12
units horizontal (2-percent slope).
Liquid-applied roofing
shall comply with ASTM C836, ASTM C957, ASTM D1227 or ASTM D3468, ASTM D6083, ASTM D6694 or
ASTM D6947.
Vegetative roofs, roof gardens and landscaped roofs
shall comply with the requirements of this chapter, Sections
1607.12.3 and 1607.12.3.1 and the International Fire Code.
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The structural
frame and roof construction supporting the load imposed
upon the roof by the vegetative roof, roof gardens or landscaped
roofs shall comply with the requirements of Table
601.
The installation of photovoltaic
shingles shall comply with the provisions of this
section.
Photovoltaic shingles
shall be applied to a solid or closely fitted deck, except
where the shingles are specifically designed to be applied
over spaced sheathing.
Photovoltaic shingles shall not be
installed on roof slopes less than three units vertical in 12
units horizontal (25-percent slope).
Unless otherwise noted,
required underlayment shall conform to ASTM D226,
ASTM D4869 or ASTM D6757.
Underlayment
shall be applied shingle fashion, parallel to and starting
from the eave, lapped 2 inches (51 mm) and fastened sufficiently
to hold in place.
Underlayment
applied in areas subject to high winds [Vasd greater
than 110 mph (49 m/s) as determined in accordance
with Section 1609.3.1] shall be applied with corrosion-resistant fasteners in accordance with the manufacturer's
instructions. Fasteners shall be applied
along the overlap at not more than 36 inches (914
mm) on center. Underlayment installed where Vasd is
not less than 120 mph (54 m/s) shall comply with
ASTM D226, Type II, ASTM D4869, Type IV or
ASTM D6757. The underlayment shall be attached in
a grid pattern of 12 inches (305 mm) between side
laps with a 6-inch (152 mm) spacing at the side laps.
Underlayment shall be applied in accordance with
Section 1507.2.8 except all laps shall be a minimum
of 4 inches (102 mm). Underlayment shall be attached
using metal or plastic cap nails with a head diameter
of not less than 1 inch (25 mm) with a thickness of not
less than 32-gage [0.0134 inch (0.34 mm)] sheet
metal. The cap nail shank shall be a minimum of 12
gage [0.105 inch (2.67 mm)] with a length to penetrate
through the roof sheathing or a minimum of 3/4
inch (19.1 mm) into the roof sheathing.
Exception:
As an alternative, adhered underlayment
complying with ASTM D1970 shall be permitted.
In areas where there has been
a history of ice forming along the eaves causing a
backup of water, an ice barrier that consists of at least
two layers of underlayment cemented together or of a
self-adhering polymer modified bitumen sheet shall be
used instead 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 contain
no conditioned floor area.
Fasteners for photovoltaic shingles shall be galvanized, stainless steel, aluminum or copper roofing nails, minimum 12-gage [0.105 inch (2.67 mm)] shank with a minimum 3/8-inch-diameter (9.5 mm) head, of a length to penetrate through the roofing materials and a minimum of 3/4 inch (19.1 mm) into the roof sheathing. Where the roof sheathing is less than 3/4 inch (19.1 mm) thick, the nails shall penetrate through the sheathing. Fasteners shall comply with ASTM F1667.
Photovoltaic shingles
shall be listed and labeled in accordance with UL 1703.
Photovoltaic shingles shall be
attached in accordance with the manufacturer's installation
instructions.
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 1504.1.1 for the appropriate maximum nominal design wind speed. Photovoltaic shingle packaging shall bear a label to indicate compliance with the procedures in ASTM D3161 and the required classification from Table 1504.1.1.
The use of above-deck thermal insulation
shall be permitted provided such insulation is covered
with an approved roof covering and passes the tests of NFPA
276 or UL 1256 when tested as an assembly.
Exceptions:
- Foam plastic roof insulation shall conform to the material and installation requirements of Chapter 26.
- Where a concrete roof deck is used and the above-deck thermal insulation is covered with an approved roof covering.
Cellulosic fiberboard
roof insulation shall conform to the material and
installation requirements of Chapter 23.
Above-deck thermal
insulation board shall comply with the standards in Table
1508.2.
Cellular glass board | ASTM C552 |
---|---|
Composite boards | ASTM C1289, Type III, IV, V or VI |
Expanded polystyrene | ASTM C578 |
Extruded polystyrene | ASTM C578 |
Fiber-reinforced gypsum board | ASTM C1278 |
Glass-faced gypsum board | ASTM C1177 |
Mineral fiber insulation board | ASTM C726 |
Perlite board | ASTM C728 |
Polyisocyanurate board | ASTM C1289, Type I or II |
Wood fiberboard | ASTM C208 |
Radiant barriers shall be permitted for use above decks where the radiant barrier is covered with an approved roof covering and the system consisting of the radiant barrier and the roof covering complies with the requirements of either FM 4450 or UL 1256.
The low emittance surface of the
radiant barrier shall face the continuous airspace between
the radiant barrier and the roof covering.
A radiant barrier installed
above a deck shall comply with ASTM C1313/1313M.
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The provisions of this section shall
govern the construction of rooftop structures.
Penthouses in compliance with
Sections 1510.2.1 through 1510.2.5 shall be considered as a
portion of the story directly below the roof deck on which
such penthouses are located. All other penthouses shall be
considered as an additional story of the building.
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Penthouses constructed
on buildings of other than Type I construction
shall not exceed 18 feet (5486 mm) in height above the
roof deck as measured to the average height of the roof of
the penthouse.
Exceptions:
- Where used to enclose tanks or elevators that travel to the roof level, penthouses shall be permitted to have a maximum height of 28 feet (8534 mm) above the roof deck.
- Penthouses located on the roof of buildings of Type I construction shall not be limited in height.
The aggregate area of
penthouses and other enclosed rooftop structures shall not
exceed one-third the area of the supporting roof deck.
Such penthouses and other enclosed rooftop structures
shall not be required to be included in determining the
building area or number of stories as regulated by Section
503.1. The area of such penthouses shall not be included
in determining the fire area specified in Section 901.7.
Penthouses shall not be
used for purposes other than the shelter of mechanical or
electrical equipment, tanks, or vertical shaft openings in
the roof assembly.
Provisions such as
louvers, louver blades or flashing shall be made to protect
the mechanical and electrical equipment and the building
interior from the elements.
Penthouses shall be constructed with walls, floors and roofs as required for the type of construction of the building on which such penthouses are built.
Exceptions:
- On buildings of Type I construction, the exterior walls and roofs of penthouses with a fire separation distance greater than 5 feet (1524 mm) and less than 20 feet (6096 mm) shall be permitted to have not less than a 1-hour fire-resistance rating. The exterior walls and roofs of penthouses with a fire separation distance of 20 feet (6096 mm) or greater shall not be required to have a fire-resistance rating.
- On buildings of Type I construction two stories or less in height above grade plane or of Type II construction, the exterior walls and roofs of penthouses with a fire separation distance greater than 5 feet (1524 mm) and less than 20 feet (6096 mm) shall be permitted to have not less than a 1-hour fire-resistance rating or a lesser fire-resistance rating as required by Table 602 and be constructed of fire-retardant-treated wood. The exterior walls and roofs of penthouses with a fire separation distance of 20 feet (6096 mm) or greater shall be permitted to be constructed of fire-retardant-treated wood and shall not be required to have a fire-resistance rating. Interior framing and walls shall be permitted to be constructed of fire-retardant-treated wood.
- On buildings of Type III, IV or V construction, the exterior walls of penthouses with a fire separation distance greater than 5 feet (1524 mm) and less than 20 feet (6096 mm) shall be permitted to have not less than a 1-hour fire-resistance rating or a lesser fire-resistance rating as required by Table 602. On buildings of Type III, IV or VA construction, the exterior walls of penthouses with a fire separation distance of 20 feet (6096 mm) or greater shall be permitted to be of Type IV or noncombustible construction or fire-retardant-treated wood and shall not be required to have a fire-resistance rating.
Tanks having a capacity of more than
500 gallons (1893 L) located on the roof deck of a building
shall be supported on masonry, reinforced concrete, steel or
Type IV construction provided that, where such supports are
located in the building above the lowest story, the support
shall be fire-resistance rated as required for Type IA construction.
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In the bottom or on the
side near the bottom of the tank, a pipe or outlet, fitted
with a suitable quick-opening valve for discharging the
contents into a drain in an emergency shall be provided.
Unenclosed roof tanks shall
have covers sloping toward the perimeter of the tanks.
Cooling towers located on the roof deck of a building and greater than 250 square feet (23.2 m2) in base area or greater than 15 feet (4572 mm) in height above the roof deck, as measured to the highest point on the cooling tower, where the roof is greater than 50 feet (15 240 mm) in height above grade plane shall be constructed of noncombustible materials. The base area of cooling towers shall not exceed one-third the area of the supporting roof deck.
Exception:
Drip boards and the enclosing construction shall be permitted to be of wood not less than 1 inch (25 mm) nominal thickness, provided the wood is covered on the exterior of the tower with noncombustible material.
Towers,
spires, domes and cupolas shall be of a type of construction
having fire-resistance ratings not less than required for the
building on top of which such tower, spire, dome or cupola is
built. Towers, spires, domes and cupolas greater than 85 feet
(25 908 mm) in height above grade plane as measured to the
highest point on such structures, and either greater than 200
square feet (18.6 m2) in horizontal area or used for any purpose
other than a belfry or an architectural embellishment,
shall be constructed of and supported on Type I or II construction.
Towers, spires, domes and cupolas greater than 60 feet (18
288 mm) in height above the highest point at which such
structure contacts the roof as measured to the highest point
on such structure, or that exceeds 200 square feet (18.6
m2) in area at any horizontal section, or which is intended
to be used for any purpose other than a belfry or architectural
embellishment, or is located on the top of a building
greater than 50 feet (1524 mm) in building height shall be
constructed of and supported by noncombustible materials
and shall be separated from the building below by construction
having a fire-resistance rating of not less than 1.5
hours with openings protected in accordance with Section
711. Such structures located on the top of a building
greater than 50 feet (15 240 mm) in building height shall
be supported by noncombustible construction.
Enclosed towers and
spires shall have exterior walls constructed as required for
the building on top of which such towers and spires are
built. The roof covering of spires shall be not less than the
same class of roof covering required for the building on
top of which the spire is located.
Mechanical
equipment screens shall be constructed of the materials specified
for the exterior walls in accordance with the type of construction
of the building. Where the fire separation distance is
greater than 5 feet (1524 mm), mechanical equipment screens
shall not be required to comply with the fire-resistance rating
requirements.
Mechanical equipment
screens shall not exceed 18 feet (5486 mm) in height
above the roof deck, as measured to the highest point on
the mechanical equipment screen.
Exception:
Where located on buildings of Type IA
construction, the height of mechanical equipment
screens shall not be limited.
Regardless of the requirements in Section 1510.6,
mechanical equipment screens that are located on the roof
decks of buildings of Type I, II, III or IV construction
shall be permitted to be constructed of combustible materials
in accordance with any one of the following limitations:
- The fire separation distance shall be not less than 20 feet (6096 mm) and the height of the mechanical equipment screen above the roof deck shall not exceed 4 feet (1219 mm) as measured to the highest point on the mechanical equipment screen.
- The fire separation distance shall be not less than 20 feet (6096 mm) and the mechanical equipment screen shall be constructed of fire-retardant-treated wood complying with Section 2303.2 for exterior installation.
- Where exterior wall covering panels are used, the panels shall have a flame spread index of 25 or less when tested in the minimum and maximum thicknesses intended for use, with each face tested independently in accordance with ASTM E84 or UL 723. The panels shall be tested in the minimum and maximum thicknesses intended for use in accordance with, and shall comply with the acceptance criteria of, NFPA 285 and shall be installed as tested. Where the panels are tested as part of an exterior wall assembly in accordance with NFPA 285, the panels shall be installed on the face of the mechanical equipment screen supporting structure in the same manner as they were installed on the tested exterior wall assembly.
The height of
mechanical equipment screens located on the roof decks of
buildings of Type V construction, as measured from grade
plane to the highest point on the mechanical equipment
screen, shall be permitted to exceed the maximum building height allowed for the building by other provisions of
this code where complying with any one of the following
limitations, provided the fire separation distance is greater
than 5 feet (1524 mm):
- Where the fire separation distance is not less than 20 feet (6096 mm), the height above grade plane of the mechanical equipment screen shall not exceed 4 feet (1219 mm) more than the maximum building height allowed;
- The mechanical equipment screen shall be constructed of noncombustible materials;
- The mechanical equipment screen shall be constructed of fire-retardant-treated wood complying with Section 2303.2 for exterior installation; or
- Where the fire separation distance is not less than 20 feet (6096 mm), the mechanical equipment screen shall be constructed of materials having a flame spread index of 25 or less when tested in the minimum and maximum thicknesses intended for use with each face tested independently in accordance with ASTM E84 or UL 723.
Rooftop-mounted
photovoltaic panels and modules shall be designed
in accordance with this section.
Rooftop-mounted photovoltaic
panels and modules shall be designed for component
and cladding wind loads in accordance with Chapter
16 using an effective wind area based on the dimensions
of a single unit frame.
Rooftop-mounted photovoltaic panels and modules shall have the fire classification in accordance with Section 1505.9.
Rooftop-mounted photovoltaic
panels and modules shall be installed in accordance
with the manufacturer's instructions.
Roof-top-mounted photovoltaic panels and modules shall be
listed and labeled in accordance with UL 1703 and shall
be installed in accordance with the manufacturer's instructions.
Rooftop structures
not regulated by Sections 1510.2 through 1510.7 shall comply
with Sections 1510.8.1 through 1510.8.5, as applicable.
Aerial supports shall be
constructed of noncombustible materials.
Exception:
Aerial supports not greater than 12 feet
(3658 mm) in height as measured from the roof deck to
the highest point on the aerial supports shall be permitted
to be constructed of combustible materials.
Bulkheads used for the shelter
of mechanical or electrical equipment or vertical shaft
openings in the roof assembly shall comply with Section
1510.2 as penthouses. Bulkheads used for any other purpose
shall be considered as an additional story of the
building.
Dormers shall be of the same
type of construction as required for the roof in which such
dormers are located or the exterior walls of the building.
Fences and similar structures shall
comply with Section 1510.6 as mechanical equipment
screens.
Flagpoles and similar structures
shall not be required to be constructed of noncombustible
materials and shall not be limited in height or number.
The structural frame
and roof construction supporting imposed loads upon the roof
by any rooftop structure shall comply with the requirements
of Table 601. The fire-resistance reduction permitted by
Table 601, Note a, shall not apply to roofs containing rooftop
structures.
Materials and methods of application used
for recovering or replacing an existing roof covering shall
comply with the requirements of Chapter 15.
Exceptions:
- Roof replacement or roof recover of existing low-slope roof coverings 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 1507 for roofs that provide positive roof drainage.
- Recovering or replacing an existing roof covering shall not be required to meet the requirement for secondary (emergency overflow) drains or scuppers in Section 1503.4 for roofs that provide for positive roof drainage. For the purposes of this exception, existing secondary drainage or scupper systems required in accordance with this code shall not be removed unless they are replaced by secondary drains or scuppers designed and installed in accordance with Section 1503.4.
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 system.
Roof replacement shall include
the removal of all 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 1507.
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The installation of a new roof
covering over an existing roof covering shall be permitted
where any of the following conditions occur:
- Where the new roof covering is installed in accordance with the roof covering manufacturer's approved instructions.
- Complete and separate roofing systems, such as standing-seam metal roof panel systems, that are designed to transmit the roof loads directly to the building's structural system and that do not rely on existing roofs and roof coverings for support, shall not require the removal of existing roof coverings.
- Metal panel, metal shingle and concrete and clay tile roof coverings shall be permitted to be installed over existing wood shake roofs when applied in accordance with Section 1511.4.
- The application of a new protective coating over an existing spray polyurethane foam roofing system shall be permitted without tear off of existing roof coverings.
A roof recover shall not be permitted
where any of the following conditions occur:
- 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.
- Where the existing roof covering is slate, clay, cement or asbestos-cement tile.
- Where the existing roof has two or more applications of any type of roof covering.
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.
Existing slate, clay or
cement tile shall be permitted for reinstallation, except that
damaged, cracked or broken slate or tile shall not be reinstalled.
Existing vent flashing, metal edgings, drain outlets,
collars and metal counterflashings shall not be reinstalled
where rusted, damaged or deteriorated. Aggregate surfacing
materials shall not be reinstalled.
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.
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Photovoltaic panels
and modules installed upon a roof or as an integral part of
a roof assembly shall comply with the requirements of this
code and the International Fire Code.