The three measurements
Carpet area is the usable floor area inside the walls of the flat — the area you could literally lay a carpet on. Under the Real Estate (Regulation and Development) Act, 2016, it is the net usable floor area excluding the external walls, the shaft area, the exclusive balcony or verandah and the exclusive open terrace, but including the internal partition walls.
Built-up area adds the thickness of the walls and, depending on who is measuring, the balcony. It is always larger than carpet area and there is no single statutory definition of it, which is why it varies between sellers.
Super built-up area adds your share of the common areas: the lobby, staircases, lifts, corridors and sometimes the clubhouse and the generator room. This is a pricing device, not a measurement of your home.
Loading, and why it matters
The gap between super built-up and carpet area is called loading. A flat sold on super built-up area at a given rate per square foot can contain very different amounts of usable space depending on how much loading the seller applied.
Two quotes are only comparable when both are reduced to the same basis. Divide the total price by the carpet area to get a rate you can actually compare, and do that for every shortlisted home.
What RERA changed
For projects registered under RERA, the promoter must disclose and sell on carpet area as defined in the Act, and the carpet area must appear in the agreement for sale. That does not stop marketing material from quoting super built-up figures, but it does mean the binding number in your agreement is the carpet area.
For resale homes and unregistered small projects, there is no such obligation. Ask for the carpet area in writing and, where the amount is large, have it measured.
Checking the number yourself
Measure room by room, inside wall to inside wall, and add the rooms. Keep balconies separate and list them separately — a balcony is genuinely useful, but it is not carpet area under the Act.
Compare your total against the approved plan rather than the brochure. Where they disagree, the approved plan is the document a court and a lender will look at.
When a listing quotes an area without saying which kind, treat it as unknown rather than assuming. On this site the area you were given is shown with the unit it was entered in.
Common questions
Which area should I compare prices on?
Carpet area. It is the only one of the three with a statutory definition and the only one that measures space you can use.
Is a balcony part of carpet area?
Not under the RERA definition. An exclusive balcony or verandah area is excluded and is normally stated separately.
How do I convert built-up to carpet area?
There is no fixed ratio — it depends on wall thickness and on what the seller included. Ask for the carpet area directly, or measure the rooms, rather than applying a rule of thumb.
Sources
- Real Estate (Regulation and Development) Act, 2016, section 2(k) — definition of carpet area
- The approved plan sanctioned by your local planning authority
Last checked 2026-09-23.