Section 23(2) in The Chennai City Corporation Building Rules, 1972
(2)The height of chimneys and flues shall be-(a)not less than sixty centimetres above the ridge of the roof, if they penetrate the same;(b)not less than one metre above a flat or pitched roof, measured from the high side;(c)not less than the height of any part of the building coming within a horizontal radius three metres and seventy five centimetres of the chimney; and(d)not less than sixty centimetres higher than any part of the building coming within a horizontal radius of one and half meters of the chimney.
