Section 2(1)(f) in Kerala Municipality Building Rules, 1999
(f)"alteration" means a structural change, such as an addition to the area or height or addition of floor/floors or mezzanine floor within any existing floor height, or change of existing floor or changing the roof to concrete slab or re-construction of existing walls or construction of concrete beams and columns amounting to structural change or construction of internal walls for subdividing the existing rooms with the intention of changing the use of the room/rooms which amount to change in the occupancy group of the building under these rules, or closing of any required means of ingress and egress to the building;