A Bengaluru couple were quoted a flat as 1,200 square feet and felt they were getting a spacious home. When they finally read the agreement, the usable carpet area was closer to 840 square feet; the rest was their share of lobbies, staircases and amenities, bundled into a bigger sounding super built up number. Nothing illegal had happened, but the flat they would actually live in was a third smaller than the headline figure suggested. Understanding the difference between carpet area and super built up area is what stops a buyer from paying for space they can never walk on.

The short answer. Carpet area is the actual usable space inside your flat, measured wall to wall. Super built up area adds your share of common spaces like lobbies and staircases, which is why it is always the larger, more flattering number. Real estate regulation now requires homes to be sold and priced on carpet area, so that is the figure to anchor on. The trade off buyers miss is real value: comparing two flats on super built up area can mislead, while comparing them on carpet area tells you what you truly get.

What is carpet area?

Carpet area is the actual usable floor area within your flat, the space you could, in principle, lay a carpet over. It is measured wall to wall inside the apartment and includes the bedrooms, living room, kitchen, bathrooms and the internal partition walls, but it excludes the thickness of the external walls, and typically excludes balconies, terraces, service ducts and shafts. In short, it is the space you actually live in and use every day.

This is the number that matters most for how big your home really feels, and it is the figure real estate regulation has put at the centre of a fair sale. When you compare flats, carpet area is the honest basis, because it strips away the shared spaces that inflate the headline size.

One subtlety worth knowing is that the regulatory definition of carpet area includes the internal partition walls within your flat, but not the external walls. This is a technical point your agreement should reflect, and it is worth glancing at, because different sources sometimes describe carpet area slightly differently. The figure that governs your purchase is the one defined in the regulation and stated in your agreement, not a looser number quoted in conversation.

What are built up and super built up area?

Built up area takes the carpet area and adds the area occupied by the walls and usually the balcony, so it is larger than the carpet area. Super built up area goes further, adding your proportionate share of the building's common areas, such as the lobby, staircases, lifts, corridors and amenities. Because it bundles in all these shared spaces, the super built up area is always the biggest of the three numbers, and it is the one traditionally used to make a flat sound larger.

The gap between carpet and super built up is often described as the loading factor. If a flat's carpet area is around seventy percent of a larger figure, the remaining thirty percent is loading, the share of common space you are paying for but cannot furnish. A higher loading means more of your money buys shared space rather than private space.

Loading is not inherently bad. Generous common areas, wide corridors, good lobbies and rich amenities all take space, and a well designed building with a somewhat higher loading may be more pleasant to live in than a cramped one with minimal common space. The point is not to chase the lowest possible loading, but to know the figure, so that you are choosing to pay for shared space consciously rather than being surprised by it after you sign.

How do the area terms compare, side by side?

The table below sets out the common area terms so you know exactly what each includes.

What does RERA require on area?

Real estate regulation changed the game here in favour of buyers. It requires that homes be quoted and priced on the basis of carpet area, and that marketing material state the carpet area clearly, rather than hiding behind a larger super built up figure. It also defines carpet area consistently, so buyers can compare like with like, and it provides that a shortfall in the delivered carpet area against what was promised is not something you simply have to accept.

For a buyer, this means you are entitled to see and rely on the carpet area, and to hold the developer to it. Knowing your rights here sits alongside the wider protections we set out in our guide on homebuyer rights under RERA. The headline super built up number may still appear in conversation, but the carpet area is the figure with legal weight.

Why does the distinction change the real price I pay?

Because price per square foot means nothing until you know which area it is measured on. A flat quoted at a lower rate per square foot on super built up area can actually be more expensive per usable square foot than a flat quoted at a higher rate on carpet area. To compare honestly, convert every option to a price per carpet square foot, so you are measuring the cost of the space you will really use, not the space you share.

This is also why two flats with the same super built up area can offer very different usable homes, if their loading factors differ. The flat with the lower loading gives you more carpet for the same headline size, and over a large purchase that difference in usable space can be worth a great deal, both in daily living and in what the home is worth when you come to sell it. Always ask for the carpet area and the loading, and let the carpet based comparison guide you. For a project such as Purva Heritage on Hosur Road, or any development, insist on the carpet area in writing.

How do I protect myself on area before buying?

Make carpet area your reference point from the first conversation. Ask for the carpet area of the specific flat, confirm it is stated in the agreement, and note the balcony area separately. Work out the loading factor so you understand how much shared space is bundled into any super built up figure you are shown. Then compare all your options on a price per carpet square foot basis, which is the only fair way to judge value.

At possession, it is reasonable to have the delivered carpet area checked against what was promised, because regulation treats a shortfall as something that can be addressed rather than shrugged off. Keeping the area terms straight, and anchoring on carpet area throughout, is one of the simplest ways to make sure you are paying for the home you think you are buying.

This same clarity helps at resale. When you eventually sell, a well informed buyer will ask about carpet area and loading just as you should now, so a home bought on a fair carpet basis is easier to explain and value later. The discipline you apply as a buyer becomes an asset you carry into your role as a future seller, and it starts with treating carpet area, not the flattering headline figure, as the number that counts.

A seven step area checklist for buyers

Run these before you commit to a flat.

1. Ask for the carpet area of the specific flat, not just the super built up figure.
2. Confirm the carpet area is stated clearly in the sale agreement.
3. Note the balcony area separately from the carpet area.
4. Work out the loading factor between carpet and super built up area.
5. Convert every option to a price per carpet square foot to compare fairly.
6. Prefer the flat that gives you more usable carpet area for your money.
7. At possession, check the delivered carpet area on the ground against what was promised.

Frequently asked questions

What is the difference between carpet area and super built up area?

Carpet area is the usable space inside your flat, measured wall to wall, including internal partition walls but excluding external walls and usually balconies. Super built up area adds your share of common spaces like lobbies, staircases and amenities, so it is always larger. Carpet area is the space you live in; super built up is the flattering headline figure.

Does RERA require prices to be quoted on carpet area?

Yes. Real estate regulation requires homes to be quoted and priced on the basis of carpet area, and marketing material to state the carpet area clearly, rather than relying on a larger super built up figure. It also defines carpet area consistently, which is why you should anchor on carpet area, the figure with legal weight.

What is the loading factor?

The loading factor is the gap between the carpet area and the super built up area, representing your share of common spaces bundled into the larger figure. If carpet area is around seventy percent of the super built up area, the loading is about thirty percent. A higher loading means more of your money buys shared space than private space.

How do I compare two flats fairly on size?

Compare them on carpet area and on price per carpet square foot, not on super built up area. Two flats with the same super built up figure can offer different usable space if their loading differs. Converting each option to a cost per usable square foot shows which flat truly gives more home for your money.

Last updated 2026-08-17. PropNewz Team.