In all districts, for zoning lots containing a landmark designated by the Landmarks Preservation Commission, or for zoning lots with existing buildings located within Historic Districts designated by the Landmarks Preservation Commission, the City Planning Commission may permit modification of the use and bulk regulations, except floor area ratio regulations, provided that:

(a)        The following conditions are met:

(1)        any application pursuant to this Section shall include a report from the Landmarks Preservation Commission stating that a program has been established for continuing maintenance that will result in the preservation of the subject building or buildings, and that such use or bulk modifications, or restorative work required under the continuing maintenance program, contributes to a preservation purpose;

(2)        any application pursuant to this Section shall include a Certificate of Appropriateness, other permit, or report from the Landmarks Preservation Commission stating that such bulk modifications relate harmoniously to the subject landmark building or buildings in the Historic District, as applicable; and

(3)        the maximum number of dwelling units shall be as set forth in Section 15-111 (Number of permitted dwelling units).

(b)        In order to grant a special permit, the City Planning Commission shall find that:

(1)        such bulk modifications shall have minimal adverse effects on the structures or open space in the vicinity in terms of scale, location and access to light and air; and

(2)        such use modifications shall have minimal adverse effects on the conforming uses within the building and in the surrounding area.

The Commission may prescribe appropriate additional conditions and safeguards which will enhance the character of the development and buildings on the zoning lot.