For developments or enlargements that have increased their permitted floor area through the transfer of development rights from the High Line Transfer Corridor by the minimum amount specified in the table in Section 98-22 (Maximum Floor Area Ratio and Lot Coverage in Subareas), and for conversions of non-residential floor area to dwelling units where the total residential floor area on the zoning lot will exceed the applicable basic maximum floor area ratio specified in the table in Section 98-22, such maximum permitted floor area may be increased through the provision of affordable housing pursuant to the Inclusionary Housing Program as modified in Section 98-26, inclusive, to the maximum amount specified in the table in Section 98-22, provided that:

(a)        In C6-4 Districts:

(1)        the amount of low income floor area is equal to at least 20 percent of the total residential floor area on the zoning lot;

(2)        the amount of low income floor area is equal to at least 10 percent of the total residential floor area on the zoning lot and the amount of moderate income floor area is equal to at least 15 percent of the total residential floor area on the zoning lot; or

(3)        the amount of low income floor area is equal to at least 10 percent of the total residential floor area on the zoning lot and the amount of middle income floor area is equal to at least 20 percent of the total residential floor area on the zoning lot.

(b)        In C6-3 Districts:

(1)        the amount of low income floor area is equal to at least 10 percent of the total residential floor area on the zoning lot;

(2)        the amount of low income floor area is equal to at least five percent of the total residential floor area on the zoning lot and the amount of moderate income floor area is equal to at least 7.5 percent of the total residential floor area on the zoning lot; or

(3)        the amount of low income floor area is equal to at least five percent of the total residential floor area on the zoning lot and the amount of middle income floor area is equal to at least 10 percent of the total residential floor area on the zoning lot.

For the purposes of this Section, low income floor area may be considered moderate income floor area or middle income floor area, and moderate income floor area may be considered middle income floor area.

However, in those subareas, or portions thereof, where the Inclusionary Housing Program is applicable, and where the Chairperson of the Department of City Planning has certified that at least 90 percent of the total development rights within the High Line Transfer Corridor have been transferred pursuant to Section 98-30, no transfer of floor area pursuant to Section 98-30 shall be required, and the basic maximum floor area ratio of a zoning lot containing the development or enlargement may be increased by up to 2.5 in Subareas B, C and D and on any zoning lot located in Subarea I over which the High Line does not pass, and up to 5.5 in Subarea A, in accordance with the provisions of paragraph (c) of this Section.

(c)        Affordable Housing Fund

Where the Chairperson of the City Planning Commission determines that more than 90 percent of the floor area eligible for transfer through the provisions of Section 98-30 have been transferred in accordance with such provisions, the Chairperson shall allow, by certification, an increase in floor area on any receiving site as specified in Section 98-33 (Transfer of Development Rights From the High Line Transfer Corridor), up to the amount that otherwise would have been permitted for such receiving site pursuant to Section 98-30, provided that instruments in a form acceptable to the City are executed ensuring that a contribution be deposited in the West Chelsea Affordable Housing Fund. Such fund shall be administered by the Department of Housing Preservation and Development and all contributions to such fund shall be used for the development, acquisition or rehabilitation of low, moderate or middle income housing located in Community District 4 in the Borough of Manhattan. The execution of such instruments shall be a precondition to the filing for or issuing of any building permit for any development or enlargement utilizing such floor area increase. Such contribution amount, by square foot of floor area increase, shall be determined, at the time of such Chairperson’s certification, by the Commission by rule, and may be adjusted by rule not more than once a year.