N.Y.C. Admin. Code § BC 1504: Section BC 1504: Performance Requirements

1504.1 Wind resistance of roofs.

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.

1504.1.1 Wind resistance of asphalt shingles.

Asphalt shingles shall be tested in accordance with ASTM D 7158. Asphalt shingles shall meet the classification requirements of Table 1504.1.1 of this code for the appropriate maximum wind speed. Asphalt shingle packaging shall bear a label to indicate compliance with ASTM D 7158 and the required classification in Table 1504.1.1 of this code.

Exception: Asphalt shingles that are not included in the scope of ASTM D 7158 shall be tested and labeled to indicate compliance with ASTM D 3161 and the required classification in Table 1504.1.1 of this code.

Table 1504.1.1 Classification of Asphalt Shingles

Maximum Allowable Stress Design Wind Speed, V

asd

Maximum Basic Design Wind Speed, V, from Table 1609.3

ASTM D 7158

a

Classification

ASTM D 3161 Classification

88

110

D, G or H

A, D or F

94

117

G or H

A, D or F

102

127

G or H

F

106

132

G or H

F

1504.2 Wind resistance of clay and concrete tile.

Wind loads on clay and concrete tile roof coverings shall be in accordance with Section 1609.

1504.2.1 Testing.

Testing of concrete and clay roof tiles shall be in accordance with Sections 1504.2.1.1 and 1504.2.1.2.

1504.2.1.1 Overturning resistance.

Concrete and clay roof tiles shall be tested to determine their resistance to overturning due to wind in accordance with SBCCI SSTD 11 and this chapter.

1504.2.1.2 Wind tunnel testing.

Where concrete and clay roof tiles do not satisfy the limitations in Chapter 16 of this code 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 this chapter.

1504.3 Wind resistance of nonballasted roofs.

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.

1504.3.1 Other roof systems.

Built-up, modified bitumen, fully adhered or mechanically attached single-ply roof systems, metal panel roof systems applied to a solid or closely fitted deck and other types of membrane roof coverings shall be tested in accordance with FM 4474, UL 580 or UL 1897.

1504.3.2 Structural metal panel roof systems.

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 E 1592 or FM 4474. Structural through-fastened metal panel roof systems shall be tested in accordance with FM 4474, UL 580 or ASTM E 1592.

Exceptions:

1. 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.

2. 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.

1504.4 Ballasted low-slope roof systems.

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 ANSI/SPRI RP-4 and Section 1504.8 of this code.

1504.5 Edge securement for low-slope roofs.

Low-slope membrane roof systems 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/FM 4435 ES-1, except the basic design wind speed V shall be determined in accordance with Chapter 16 of this code.

1504.6 Physical properties.

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 G 152, ASTM G 155 or ASTM G 154. 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.

1504.7 Impact resistance.

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 D 3746, ASTM D 4272, CGSB 37-GP-52M or the "Resistance to Foot Traffic Test" in Section 5.5 of FM 4470.

1504.8 Surfacing and ballast materials.

Aggregate, gravel or crushed stone shall not be used as surfacing for roof coverings.

1504.9 Reflectance.

Roof coverings on roofs or setbacks with slope equal to or less than two units vertical in 12 units horizontal (17 percent) shall have:

1. a minimum initial solar reflectance of 0.7 in accordance with ASTM C1549 or ASTM E 1918, and a minimum thermal emittance of 0.75 as determined in accordance with ASTM C1371 or ASTM E 408; or

2. a minimum SRI of 82 as determined in accordance with ASTM E 1980.

Roof coverings on roofs or setbacks with slope greater than two units vertical in 12 units horizontal (17 percent) shall have:

1. A minimum initial solar reflectance of 0.25 in accordance with ASTM C 1549 or ASTM E 1918, and a minimum thermal emittance of 0.75 as determined in accordance with ASTM C 1371 or ASTM E 408; or

2. A minimum SRI of 39 as determined in accordance with ASTM E 1980.

Exceptions:

1. Terraces on setbacks comprising less than 25 percent of the area of the largest floor plate in the building.

2. Any portion of a roof covered by a green roof system, including such a system with agricultural plantings, in compliance with Section 1507.16 of this code.

3. Any portion of a roof used as outdoor recreation space by the occupants of the building that is landscaped, covered by wood decking or covered with a walking surface or other protective surface, provided that such walking surface or protective surface has a minimum initial solar reflectance of 0.3 as determined in accordance with ASTM C 1549 or ASTM E 1918.

4. Ballasted roofs, provided that the ballast has a minimum initial solar reflectance of 0.2 as determined in accordance with ASTM C 1549 or ASTM E 1918.

5. Any portion of a roof that is under mechanical equipment, flush mounted solar panels lying directly on the roof surface, duckboarding, decking, platform, roof tank, cooling tower or any other rooftop structure or equipment exempted by rule by the commissioner.

6. Any roof or portion of a roof composed of glass, metal, clay or concrete tile or plastic/rubber intended to simulate clay or concrete tile, wood, or slate.

7. Any portion of a roof used by a school or daycare center as a playground for children.

8. Any roof, if the amount of rooftop space not subject to exceptions 1 through 7 is in the aggregate less than 100 square feet.