N.Y.C. Admin. Code § 28-118.16.1: § 28-118.16.1 Buildings exceeding three stories in height and change does not exceed 20 percent of total floor area.

Where a building exceeds three stories in height and the change does not exceed 20 percent of the total floor area, an amendment to the existing certificate of occupancy for such new use shall be issued by the commissioner certifying that the proposed new occupancy and use conforms to the provisions of the laws governing building construction and that the proposed use will not be in conflict with any provisions of the New York state labor law, New York state multiple dwelling law or the zoning resolution.