Section 71(2) in West Bengal Municipal (Building) Rules, 2007
(2)Any chimney shall be built at least 0.9 metre above any flat roof :Provided that the top of any chimney shall not be below the top of any adjacent wall and, in the case of a sloping roof, the top of the chimney shall not be less than 0.6 metre above the ridge thereof in which the chimney penetrates.
