According to Kerala Building Rules, the Area of Residences shall be calculated as follows (excerpts from KMBR 1999) -
'Carpet Area' means the usable floor area excluding the area of staircases, lift wells, escalators, ducts, toilets, air condition plant room and electrical room.
[Note:- For calculating carpet area, twenty percent of the floor area shall be deducted from the total floor area in each floor;]
'Plinth' means the portion of a structure between the surface of the surrounding ground and surface of the floor, first above the ground;
'Plinth Area' means area of the building at the plinth level, does not include the area of open porch [(not enclosed by wall)] uncovered staircase and the like;
'Floor Area' means the built up area of a building at any floor level;
'Floor Area Ratio (F.A.R.)' means the quotient obtained by dividing the total floor area on all floors by the area of the plot;
Parts to be included for calculating Floor Area:
In the calculation of floor area of buildings the following shall be taken into account, namely:-
(i) the total floor area of building shall be the sum total of floor areas at every floor including basement, if any;
(ii) the internal sanitary shafts, air conditioning ducts and lifts shall be included in all the floor levels;
(iii) the area of 'Barsati' or penthouse at terrace floor level shall be included in the floor area; and
(iv) towers, turrets, domes, etc., projecting above the terrace shall not be included in the floor area at the terrace level.
(b) Floor Area of Ground Floor:
(i) the floor area of ground floor shall be calculated at the plinth level excluding the plinth offsets ( if the offset does not exceed 5cm);
(ii) in cases where the building consists of columns projecting beyond cladding, the floor area shall be taken up to the external face of the cladding and shall not include the projections of columns;
(c) Floor Area of Upper Floor:
(i) The floor area of upper floors shall be calculated at the relevant floor levels, architectural bands, cornices, etc., shall not be included in the floor area, vertical sunbreakers or box louvers also shall not be included; and
(ii) in the case of verandahs and balconies with at least one of its sides open (other than parapets) to exterior or interior open spaces, only 50% of the area shall be taken into account for calculation of floor area.
(d) Floor Area of Galleries, Mezzanine Floor and Lofts:
(i) area of galleries i.e., upper floor of seats in an assemby hall, auditorium etc., shall be fully included in the floor area;
(ii) area of mezzanine floors shall be included in the floor area; and
(iii) the area of loft shall not be included.
Luxury Tax for Residences in Kerala:
Under the Kerala Building Tax Act, 1975 (KBT Act), luxury tax at the rate of Rs. 2,000 per annum is leviable on all residential buildings having plinth area of 278.7 sqm (Approx. 3000 sqft) or more and completed on or after 1 April 1999. The tax shall be paid in advance on or before 31 March every year.
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ASKIN- Architect Shahdad Karim INdia