Section 32(1)(a) in Kerala Municipality Building Rules, 1999
(a)The maximum height of the building or part thereof shall not exceed twice the width of the street abutting the plot plus twice the width of the yard from the building to the abutting street and this height may further be increased proportionately at the rate of 3 metres for every 50 cms. by which the building or the corresponding portion or floor of the building is set back from the building line;