The standard provides a standardized approach for calculating plinth, carpet, and rentable areas in buildings across India, applicable to both residential and commercial structures, old or new. It offers comprehensive rules on inclusions and exclusions for each measurement type to ensure uniformity for construction, valuation, and leasing purposes.
Overview
The standard provides a standardized approach for calculating plinth, carpet, and rentable areas in buildings across India, applicable to both residential and commercial structures, old or new. It offers comprehensive rules on inclusions and exclusions for each measurement type to ensure uniformity for construction, valuation, and leasing purposes.
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Contents
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Frequently Asked
Per the standard, the plinth area comprises the built-up floor space measured at basement or storey level including wall areas (excluding plinth offsets), fully accounting for shafts like sanitary and lift shafts, and considering verandahs and balconies at 100% if protected and 50% if unprotected. Alcove areas are included based on their height: 25% for up to 1 m, 50% for 1 to 2 m, and fully if exceeding 2 m. Shared walls are counted at half their area for each owner to ensure fair apportionment.
Carpet area is defined as the usable floor area within the internal walls, excluding spaces such as corridors, passages, entrance halls, staircases, lift shafts, bathrooms, kitchens, air-conditioning ducts, and utility shafts. Essentially, it represents the net floor area available for occupancy and excludes all service and circulation spaces to maintain uniformity in measurement.
For residential buildings, rentable area includes the carpet area plus areas like kitchen, pantry, storage, lavatories, bathrooms, and verandahs—with verandahs counted at 50% if unglazed and 100% if glazed. In non-residential buildings, rentable area comprises the carpet area plus the canteen area including its attached store, kitchen, and pantry. Certain categories of areas like stair covers and machine rooms are excluded from carpet but managed differently in rentable area calculations.
Mezzanine floors, defined as intermediate floors with a minimum clear height of 1.8 meters where permitted locally, are measured independently and not combined with other floor areas. They typically include additional seating levels in assembly spaces. For non-residential buildings, only 25% of the mezzanine carpet area is considered in rentable area calculations, ensuring precise accounting of these intermediate spaces.
Shared or common walls jointly owned by multiple owners are accounted for at half their total area in the plinth area measurement for each owner. This ensures equitable division of the shared wall space. Exclusive walls are included in full, and measurements include wall thickness and finishes but exclude plinth offsets.
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