Carpet area vs built-up vs super built-up: what you are actually paying for
This is the single most common source of confusion in an Indian property purchase, and it is worth twenty minutes of your attention. Two apartments advertised at the same headline size can differ substantially in the space you can actually stand in. The difference is not fraud — it is definitional — but it is only visible if you know which number you are being shown.
The three definitions
Carpet area
The usable floor area within the walls of the apartment — broadly, everywhere you could lay a carpet. Under the Real Estate (Regulation and Development) Act, 2016, carpet area is defined as the net usable floor area, excluding the area covered by external walls, areas under service shafts, and exclusive balcony, verandah and open terrace areas, but including the area covered by internal partition walls.
This is the figure that matters, and it is the figure a RERA-registered project is required to disclose.
Built-up area
Carpet area plus the thickness of the walls and, typically, the balcony. It usually runs around 10–20% above carpet area depending on construction and layout.
Super built-up area
Built-up area plus your proportionate share of common areas — lobbies, staircases, lifts, corridors, and in many cases amenity spaces such as the clubhouse. This is the number that was historically advertised, and it is the one with no fixed relationship to what you get.
Loading, and why it varies so much
The gap between carpet and super built-up is called loading. If a flat has 1,000 sq.ft. of carpet area and is sold as 1,400 sq.ft. super built-up, the loading is 40%.
| Carpet area | Loading | Advertised super built-up |
|---|---|---|
| 1,000 sq.ft. | 25% | 1,250 sq.ft. |
| 1,000 sq.ft. | 35% | 1,350 sq.ft. |
| 1,000 sq.ft. | 45% | 1,450 sq.ft. |
All three rows describe the identical apartment. Loading has risen over the years as projects have added larger lobbies and more elaborate amenity decks — which you may genuinely want, but you should know you are paying for them.
Since RERA came into force, prices and disclosures for registered projects are stated against carpet area. If a salesperson quotes you a rate on super built-up, ask for the carpet figure before you compare anything.
How to compare two projects properly
- Get the RERA carpet area for both, in writing, and verify it against the MahaRERA disclosure.
- Divide the all-in price by carpet area to get a true per-square-foot rate. Compare that number, not the advertised one.
- Ask separately what the balcony, deck and terrace areas are — they are excluded from carpet area but they are real space you will use.
- Check the slab-to-slab height. An 11 ft slab-to-slab apartment feels materially larger than a 9.5 ft one at identical carpet area.
- Confirm what is included: covered parking, floor rise, club membership, and the maintenance deposit are frequently quoted separately.
The things carpet area does not capture
Carpet area is the right basis for comparison, but it is not the whole picture. Two homes with identical carpet areas can live very differently depending on how the plan is drawn. A layout that runs the living room horizontally along a deck gives you a wide, bright primary space; the same area arranged as a narrow corridor room does not. Circulation space that exists only to connect rooms is carpet area you paid for and rarely use.
When you review a floor plan, look for the proportion of the total that is genuinely occupiable, the width of the primary living space, whether bedrooms take a bed and a wardrobe without blocking a door, and how much external wall carries windows. Those four things determine how a home feels far more than a headline number does.
The one-line version
Compare carpet area, verify it on MahaRERA, calculate your own per-square-foot rate from the all-in cost, and then judge the floor plan on how the space is arranged. Everything else is marketing.