In order to conform with the existing scale and character of the Preservation Subdistrict, any zoning lot located in the underlying C5-P District shall be limited to a maximum floor area ratio of 8.0.

For all purposes other than as set forth in this Section, the R10 District regulations shall apply to any portion of a building containing residential uses.

Mandatory street walls are required as follows:

The street wall of any building shall be located on the street line and shall extend along the full length of the front lot line to a minimum height of 72 feet above the curb level, or the full height of 72 feet above the curb level, or the full height of the building, whichever is less. Above a height of 85 feet, the street wall shall be set back at least 15 feet from the street line and shall be subject to the sky exposure plane regulations of Section 33-432 (In other Commercial Districts) applicable in C5 Districts. The provisions of Sections 33-44 (Alternate Front Setbacks) and 33-45 (Tower Regulations) are not applicable in the Preservation Subdistrict.

On application, the City Planning Commission may grant special authorization for minor modifications of the mandatory street wall provisions of this Section as applied to an enlargement, upon the applicant's showing of compelling necessity. Such authorization, however, may in no event include modification of permitted floor area regulations.