Section 349A(1) in The Mumbai Municipal Corporation Act, 1888
(1)Except with the written permission of the Commissioner, no building shall be erected or raised to a greater height than seventy feet as measured from the level of the centre of the street in front-(a)in the case of a pitched roof, up to the tie-beam of the roof, and(b)in the case of a flat roof up to the surface of the roof.