Section 101(1) in Kerala Municipality Building Rules, 1999
(1)Alteration or addition/extension of first floor or second floor or both and or conversion or erection of roof, shutter or door shall be allowed to buildings permitted under orders granting exemption from provisions of Kerala Building Rules, 1984, issued by Government or District Collectors subject to sub rules (2) and (3) of this rule, whether the work has commenced or not or whether being carried on or completed:Provided that the permitted building and that proposed alteration or addition/extension or other work mentioned in this rule shall have minimum 3 meters distance from the boundary abutting any National Highway, State Highway, District road or other road notified by the Municipality and minimum 1.5 meters from the boundary of other road.