New York Laws
Title 2 - Fire Protection
235 - Stairs in Non-Fireproof Tenements.

§ 235. Stairs in non-fireproof tenements. 1. Every non-fireproof
tenement erected after May fifteenth, nineteen hundred two, containing
more than twenty-six apartments or suites of rooms above the entrance
story shall have an additional stair for every additional twenty-six
apartments or suites or fraction thereof; except that if such tenement
contains not more than thirty-six apartments above the entrance story,
in lieu of an additional stair the stairs, stair halls and entrance
halls throughout the entire tenement may each be at least one-half wider
than is specified in sections two hundred thirty-four, two hundred
thirty-seven and two hundred thirty-eight.

2. The number of apartments on any story in any non-fireproof tenement
may be altered, if the number of living rooms on such story is not
increased by more than twenty per centum. If the number of living rooms
on any story or section thereof above the entrance story exceeds twenty,
there shall be an additional stair for each twenty rooms or fraction
thereof on any such story or section thereof, except that if the number
of living rooms on any such story or section does not exceed thirty, in
lieu of an additional stair one stair and every public hall connected
therewith may be at least one-half wider than is specified in sections
two hundred thirty-four, two hundred thirty-seven and two hundred
thirty-eight.

3. Whenever the total number of rooms, exclusive of bathrooms,
water-closet compartments, and cooking spaces less than eighty square
feet in area, in any non-fireproof tenement or section thereof is
decreased through the process of an alteration, the number of apartments
may be altered and the provisions of this section which relate to
additional stairs shall not be applicable.