Carpet Area vs Super Built-Up Area in Bengaluru (2026 Guide)

Last updated 16 July 2026 · Facts checked against the sources listed at the end

What do carpet, built-up and super built-up actually mean?

Indian project marketing uses three different sizes for the same home, and only one of them is defined in law. The Real Estate (Regulation and Development) Act, 2016 defines carpet area as the net usable floor area of an apartment: it excludes external walls, service-shaft areas and the exclusive balcony or verandah, but it includes the internal partition walls. Balconies are measured and disclosed separately as exclusive balcony area. Everything else is industry convention, not statute.

The ratio between them is the “loading”. If a 700 sq ft carpet home is sold as 1,100 sq ft super built-up, the loading is about 57% and your efficiency (carpet divided by super built-up) is about 64%. Neither number is on the poster; both decide what you actually get for the rate.

Why does the same flat show three different sizes online?

Because listings rarely state their basis, and sometimes state it wrongly. This corridor supplied a live example this month. For Godrej MSR City, one major portal labels the quoted 1,186–1,876 sq ft sizes as carpet area, while broker guides and buyer forums describe the same numbers as super built-up, putting true carpet nearer 823–1,260 sq ft (2026). Both cannot be right, and the difference swings the effective rate by a quarter or more. Our Altura vs Godrej MSR City comparison treats that dispute at length.

Contrast two neighbours. Purva Northern Lights’ broker pages publish both bases side by side: 2 BHK carpet of roughly 670–768 sq ft against super built-up of roughly 1,097–1,437 sq ft, which implies loadings of about 1.55 to 1.77 times (broker-published, July 2026). And TVS Emerald Altura’s official floor-plan document prints a saleable area against every unit (1,103–2,133 sq ft across the 2 and 3 BHK range) and records in its notes that the RERA carpet and balcony areas are measured separately, with carpet including all internal walls. The published plates are on our Altura floor-plan page; ask the sales office for the unit-wise RERA area statement to put the carpet number beside the saleable one.

The honest general rule: a size without a stated basis is not yet a fact. Birla Trimaya’s portal sizes, for instance, circulate without a stated basis at all (2026), which is why our Altura vs Trimaya comparison flags them rather than computing rates from them.

The loading maths: how ₹11,000 becomes ₹17,000

Rates quoted on different bases are different currencies. Take the corridor’s own numbers. Purva Northern Lights prices at about ₹11,000 per sq ft base on super built-up area (portal quotes, July 2026). At its broker-published loadings of 1.55 to 1.77 times, that same money works out to roughly ₹17,000 to ₹19,500 per carpet square foot (our arithmetic on those published figures). Neither version is wrong; they are the same price wearing two units.

Now the trap in reverse. If a listing shows a size that is secretly super built-up but you read it as carpet, the flat looks about a third bigger and the rate about a third cheaper than reality. That is exactly the ambiguity in the MSR City case above: read its ₹10,800–12,119 per sq ft quotes (2026) against carpet instead of super built-up and the true carpet-basis rate lands closer to ₹14,000–15,000. A rate is meaningless until you know its denominator.

What does RERA actually require, and what does it not?

RERA puts the carpet number on the record: the registration filing carries a unit-wise area schedule, and the agreement for sale states the carpet area of your specific apartment. Developers’ own documents increasingly mirror the convention; Altura’s floor-plan notes, for example, spell out that saleable, RERA carpet and RERA balcony areas are recorded per unit and that carpet includes all internal walls (developer document, 2026).

What RERA does not do is police the poster. Advertising and portal listings in Karnataka still overwhelmingly quote super built-up, and no rule forces a hoarding to print the carpet number beside it. So the protection exists, but you have to go get it: the certificate, the schedule and the agreement carry the real sizes, while the marketing layer carries the big ones. Statutory costs then stack on top of whichever price you agree; our Karnataka cost-of-buying guide works that 7–13% layer.

Is a high loading automatically a bad deal?

No, and the honest version of this guide has to say so. The loading pays for things you will actually use: lift cores, fire staircases, lobbies, corridors and, in most Bengaluru quotes, a share of the clubhouse. A township with two grand clubhouses genuinely carries more common area per home than a compact estate, and its higher loading reflects a real difference in what is being built, not just accounting. Twelve towers sharing 36 amenities and a mid-rise format will not load the same way as thirty highrise towers sharing five clubhouses.

What is a problem is unpriced opacity: a loading you cannot see, applied to a rate you cannot decompose. Two questions dissolve it. What is the carpet area of this exact unit, in writing? And what common facilities does the difference pay for, phase by phase? A developer with a real amenity programme can answer both without flinching. If the answers wander, that tells you something the brochure does not.

When you read the RERA area schedule itself, the columns are plainer than the marketing: unit number, floor, carpet area, exclusive balcony or verandah area, and in most Karnataka filings the apartment type against each. Find your shortlisted unit’s row, add carpet and balcony, and set that against the saleable number on the cost sheet. The gap between those two figures is the loading you are being asked to pay for, now expressed in square feet instead of adjectives.

How do you verify a project’s real areas in five minutes?

Four checks, in order. First, the RERA registration: pull the project on rera.karnataka.gov.in and open its area schedule; our RERA walkthrough shows the steps with screenshots. Second, the draft agreement for sale: the carpet area clause is where the legal number lives; read it before any token. Third, the official floor-plan document: unit-wise areas, and notes that tell you the measurement conventions. Fourth, the cost sheet: confirm in writing which area basis the rate is applied to, and whether balcony and terrace areas are charged separately.

Then normalise before you compare projects: divide every quoted price by its carpet area, not its marketing area. Two homes at “₹1.35 Cr” with carpets of 700 and 900 sq ft are not the same price. They are ₹19,300 and ₹15,000 per carpet foot.

What should corridor buyers do with this in 2026?

Treat the size line with the same scepticism as the price line. On this corridor right now, one project publishes both bases (Northern Lights, via brokers), one publishes saleable with the carpet convention documented (Altura), one has its basis actively disputed between sources (MSR City) and one circulates sizes with no basis at all (Trimaya). The projects are not equally legible, and that legibility is itself information about how easy your paperwork will be.

If Altura is on your shortlist, the floor-plan plates carry every published unit size, and you can request the current cost sheet and unit-wise area statement to put carpet, saleable and price on one page. For the wider field, our under-₹2-crore shortlist and price tracker label every figure’s source and basis where stated.