N.Y.C. Admin. Code § 27-475: § 27-475 Attached garages.

Private garages attached to, or located above or below, a dwelling shall have walls, partitions, floors, and ceilings separating the garage from the dwelling, having a fire-resistance rating of at least one hour, except that such fire-resistive construction shall not be required between a dwelling and a carport when such carport is open on at least two sides. Any openings to the dwelling in required walls or partitions shall be protected with one and three-quarter inch solid core wood doors or equivalent.