Carpet Area vs Built-Up vs Super Built-Up

Carpet area is defined under RERA as the net usable floor area within the walls of the apartment. It excludes external walls, service shafts and any exclusive balcony or verandah, but it includes internal partition walls.

Built-up area is carpet area plus the thickness of the walls and the balcony. Super built-up area — sometimes called saleable area — takes the built-up area and adds a proportionate share of common spaces: lobbies, staircases, lift wells, clubhouses and other amenities.

The share of common space loaded onto each flat is the "loading factor". It is set by the developer, varies between projects, and is the reason two flats with identical carpet areas can be advertised with quite different super built-up figures.

Before RERA, developers commonly quoted and sold on super built-up area. Because the loading factor was not standardised, a buyer could not reliably compare two projects, and the space actually delivered was frequently smaller than the number that had been paid for.

RERA requires developers to disclose and sell on carpet area. That does not eliminate the other measures from marketing material, and super built-up figures still appear in brochures and portal listings, but the agreement and the price should be on carpet.

Convert everything to carpet area before comparing anything. A rate per super built-up square foot cannot be compared with a rate per carpet square foot, and a project with an aggressive loading factor will look competitive on the former while being expensive on the latter.

Ask for the carpet area in the agreement, ask for the price against that carpet area, and do the division yourself. Where a developer will not state a carpet figure clearly, that reluctance is itself informative.