For the conversion of non-residential floor area to residences, the applicable density requirements shall be modified in accordance with the provisions of Section 15-111 (Number of permitted dwelling units), and the regulations governing open space ratio, yards, the minimum distance between two or more buildings on a single zoning lot and the minimum distance between windows and walls or lot lines are hereby superseded and replaced by the requirements of Sections 15-112 (Light and air provisions) and 15-12 (Open Space Equivalent).