The provisions of this Section shall apply within an area bounded by Tenth Ave, West 31st Street, the Lincoln Tunnel Approach and West 33rd Street.

No building shall exceed a height of 150 feet within 10 feet of West 33rd Street, 15 feet of Tenth Avenue and 20 feet of West 31st Street, except as provided below:

(a)        along West 31st Street, a building may rise without setback provided no part of such building is within 15 feet of West 31st Street; and

(b)        along West 33rd Street, a building may rise without setback, provided that the aggregate width of street walls above a height of 150 feet and within 10 feet of the West 33rd Street street line does not exceed 50 percent of the length of the West 33rd Street frontage of the zoning lot.

However, if more than 75 percent of the total floor area existing on the zoning lot on January 19, 2005, is demolished, the reconstructed buildings shall not exceed a height of 150 feet within 15 feet of a wide street line and 20 feet of a narrow street line.