Section 102(2) in Kerala Municipality Building Rules, 1999
(2)Addition/extension of upper floors to any building shall be permitted, if the proposed addition/extension satisfies the provisions in these rules, irrespective of whether the building proposed to be extended conforms to the provisions in these rules or not:Provided that in the case of existing ground floor on the side of cul-de-sac not exceeding 250 meters length or pedestrian lanes or streets up to 3 meter width, first floor shall be permitted above it if the existing ground floor and proposed first floor have minimum 1.50 metes distance from the boundary abutting such cul-de-sac, lane or street irrespective of whether it satisfies the provisions in rule 25 and rule 32:Provided further that for the purpose of calculating maximum coverage and floor area ratio permissible and for calculating the total off street parking requirements both the proposed extension and the building proposed to be extended shall be taken into account.