Floor Area.
Every multiple-family dwelling hereinafter erected, constructed, reconstructed or altered in a District “R-3” shall have a floor area, excluding common corridors, basements, open and screened porches and garages, of not less than eight hundred (800) square feet for each efficiency or one (1) bedroom unit, eleven hundred (1,100) square feet for each two (2) bedroom unit, fourteen hundred (1,400) square feet for each three (3) bedroom unit.