NYC Stairway Access to Roof

1009.12.1 Occupancy Groups I-1, R-1 and R-2. In buildings in Occupancy Groups I-1, R-1 and R-2 two stories or more in height, with roofs having a slope of 15 degrees (0.26 rad)‡ or less, all interior stairs, except those terminating at the level of a setback roof, shall extend to the roof surface.

Exceptions:

1. In buildings in Occupancy Groups R-1 and R-2 two stories in height and in Occupancy Group R-2 three stories in height with not more than one dwelling unit per story, access to the roof shall be permitted to be a noncombustible roof hatch or trap door not less than 21 inches (533 mm) in width and 28 inches (711 mm) in length. Such hatches shall be located within the stair enclosure and be provided with a stationary, noncombustible access ladder or alternating tread device.

2. In buildings in Occupancy Group R-2 complying with Item 4 of Section 1018.2, roof access shall be governed by Item 4.6 of such section.

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