Carpet area vs super built-up: loading factor calculator
A builder quotes super built-up area. RERA makes them state carpet area. This works out the gap between the two — the loading factor — and what that gap costs you.
Why the two areas differ
A builder quotes a rate on super built-up area — the flat plus your share of the lifts, lobbies, staircases, corridors, clubhouse and shafts. RERA requires them to disclose carpet area, the usable floor inside your walls, and to sell against it. The gap between the two is loading, and it is the reason two flats advertised at the same rate per square foot can hand you very different homes.
Compare on carpet, not on the quoted rate
The rate on a brochure is not comparable between projects, because each divides the price by an area it defined itself. The real rate per square foot of carpet is comparable, because carpet area means the same thing everywhere by law. That is the figure this calculator gives you, and it is the one to take into a second conversation.
Carpet, built-up and super built-up, side by side
| Area | What it covers | Who defines it |
|---|---|---|
| Carpet area | Usable floor inside your own walls | RERA, Section 2(k) |
| Built-up area | Carpet area plus your walls and balcony | The builder |
| Super built-up area | Built-up area plus your share of lifts, lobbies, corridors and the clubhouse | The builder |
Only the first row is defined in law. That is why a rate quoted on super built-up area is not comparable between two projects, and a rate on carpet area is.
What to ask for
- The carpet area in writing, in the same units as the quoted area.
- Whether the balcony and the terrace are inside the carpet figure or outside it.
- Which common spaces the loading covers, and whether the clubhouse is charged again separately.
The carpet area a promoter filed with the authority sits on the project's own record. You can look up any registered project on Estanzo's project pages and compare the filing against what you were handed.
After the area, the price
Loading tells you what you are getting. It does not tell you what completing the purchase costs — stamp duty, registration, GST and the charges below the headline. The stamp duty & buying cost calculator adds those up, and the EMI calculator works out the loan.
Questions about carpet area, super built-up area and loading
What is loading in an apartment?
Loading is the share of the area you pay for that is not inside your flat — lifts, lobbies, staircases, corridors, the clubhouse and service shafts. It is the gap between the carpet area you can use and the super built-up area the price is quoted on.
How is loading calculated?
Loading percentage = (super built-up area − carpet area) ÷ carpet area × 100. A flat with 1,000 sq ft carpet sold as 1,300 sq ft super built-up carries 30% loading: for every 100 sq ft you can live in, you pay for another 30 that you share.
What is a normal loading percentage in India?
Property publications put the usual range at 25% to 40%, and report the national average climbing towards 40%. It varies by city: Mumbai is quoted highest at 40% to 50%, Bengaluru around 30% to 40%, with budget projects nearer 25%. These are figures the market reports, not a rule — RERA sets no limit on loading.
What is a good loading factor to look for?
There is no official answer, because RERA caps nothing. A lower loading factor means more of what you pay for is inside your flat; a higher one may be buying real shared space. Compare the rate per square foot of carpet area between two projects — that is the only figure that means the same thing in both.
Does RERA regulate loading?
RERA does not cap loading, but it does require the promoter to disclose carpet area, defined in Section 2(k) of the Act, and to sell on that basis. So a builder can load a flat as heavily as they like — they cannot hide the carpet figure while doing it.
Is high loading always bad?
No. Loading pays for shared space that may be worth having — a real clubhouse, wide lobbies, more lifts. What matters is knowing the number, so you are comparing two projects on the area you actually get rather than on two differently inflated rates.
What is the difference between carpet, built-up and super built-up area?
Carpet area is the usable floor inside your walls. Built-up area adds the walls themselves and the balcony. Super built-up area adds your share of every common space in the project. Only carpet area is defined by RERA; the other two are the builder’s own measures.
Every figure above is worked out from the numbers you entered. Nothing on this page comes from the RERA register, and the starting values are common ones, not a quote. Rates, charges and duties change — check yours before you act on any of this. Rates and ranges on this page last checked .