That "1,200 sq ft" flat may give you only about 850 sq ft to actually live in. The rest is the loading — your share of lobbies, staircases, lifts and the clubhouse, bundled into the super built-up area a builder quotes. This guide breaks down carpet, built-up and super built-up area, explains the loading factor, and shows how to use the RERA carpet area to compare price per sq ft honestly — so you never overpay for space you don't get.
- Carpet area is your usable space — and under RERA it's the legal basis for pricing. Super built-up is a marketing figure.
- Loading factor = (super built-up − carpet) ÷ carpet. In Bengaluru it typically runs 25-40% and has been rising.
- A home sold "super built-up" gives you only ~60-70% of that number as carpet.
- Compare on price per carpet sq ft, not the headline rate: ₹10,000/sq ft at 40% loading is really ₹14,000 per carpet sq ft.
- Don't estimate — verify. Every RERA-registered project's carpet area is public on the Karnataka RERA portal.
Carpet area vs built-up vs super built-up area
Carpet area is the net usable floor area inside your flat (what you can lay a carpet on). Built-up area adds the thickness of your walls and balcony. Super built-up area adds your share of the building's common areas — and it's the biggest, most flattering number builders quote.
| Term | What it includes | Usable by you? |
|---|---|---|
| Carpet area | Net usable floor area inside the flat, including internal partition walls; excludes external walls, shafts and exclusive balcony/terrace | Yes — this is your real space |
| Built-up area | Carpet area + external/internal wall thickness + balcony | Partly (walls aren't livable) |
| Super built-up (saleable) | Built-up area + your share of common areas (lobby, stairs, lifts, clubhouse, corridors) | No — shared/common space |
What is the loading factor — and what's normal in Bengaluru?
The loading factor is the mark-up of super built-up over carpet area: (super built-up − carpet) ÷ carpet. In Bengaluru it typically ranges from about 25% in budget projects to 38%+ in amenity-heavy premium ones, and the city average has been rising — ANAROCK research has pegged it near the high-30s/low-40s in recent years, up from roughly 30% in 2019.
| Segment | Typical loading | Carpet as % of super built-up |
|---|---|---|
| Budget / mid-segment | ~25-30% | ~77-80% |
| Premium (more amenities) | ~30-38% | ~72-77% |
| Luxury / high-rise | ~38-45%+ | ~69-72% |
There is no legal cap on loading — RERA's protection is disclosure, not a ceiling. So two "1,200 sq ft" flats can hand you very different amounts of real space. The only way to compare them fairly is on carpet area.
The calculator: what you actually get, and what you actually pay
Enter the super built-up area, the quoted rate and the loading factor to see your true carpet area and the real price per carpet sq ft. Carpet = super built-up ÷ (1 + loading); real carpet rate = quoted rate × (1 + loading).
Loading-factor calculator
See the carpet area you actually get — and your true price per carpet sq ft.
Carpet = super built-up ÷ (1 + loading). Real carpet rate = quoted rate × (1 + loading). Figures are indicative — verify the registered carpet area on RERA before you buy.
Worked example: a 1,200 sq ft flat quoted at ₹10,000/sq ft with 35% loading is really about 889 sq ft of carpet — and ₹13,500 per carpet sq ft. The headline rate hid a third of the price.
What RERA actually says (and doesn't)
Under RERA, carpet area is the mandatory basis for pricing and disclosure — promoters must state it in advertisements, the agreement for sale and registration. "Super built-up" is not banned, but it can no longer be the figure you transact on.
Section 2(k) of the RERA Act, 2016 defines carpet area as the net usable floor area of an apartment — excluding external walls, areas under service shafts and exclusive balcony, verandah and open-terrace areas, but including the internal partition walls. Crucially, the Act mandates transparency; it does not cap the loading factor. That means the regulation gives you the right number to compare on — carpet area — but you still have to do the comparison.
How to verify carpet area before you buy
Don't rely on a brochure or a sales pitch — every RERA-registered project's carpet area per unit type is public. Check it on the Karnataka RERA portal, and match it to the figure in your agreement for sale.
Go to the Karnataka RERA portal, search the project by name or registration number, and open its registered details — the carpet area, approved plan and timelines are all disclosed there. If the registered carpet area doesn't match what the sales team told you, that's a red flag worth pausing on. Short on time? Our free RERA & legal check pulls the registered carpet area, RERA status and builder track record for any Bengaluru project, and our live map shows the RERA number on each project.
Carpet vs super built-up: how to compare two flats honestly
Divide each flat's total price by its carpet area, and compare those two numbers. A flat with a higher headline rate but lower loading can easily work out cheaper per usable sq ft than a "cheaper" flat with heavy loading.
| Flat A | Flat B | |
|---|---|---|
| Quoted rate (super built-up) | ₹9,500/sq ft | ₹10,500/sq ft |
| Loading factor | 42% | 27% |
| Real price / carpet sq ft | ₹13,490 | ₹13,335 |
On the sticker, Flat A looks ₹1,000/sq ft cheaper. On carpet — the space you actually live in — Flat B is the better buy. That reversal is the whole point of this guide.
Frequently asked questions
Does RERA carpet area include the balcony?+
No. Under the RERA definition, carpet area is the net usable floor area and excludes the exclusive balcony, verandah and open terrace areas (and external walls and service shafts), but it does include the internal partition walls. Balconies are disclosed and priced separately.
What percentage of built-up area is carpet area?+
Roughly 75-85% of built-up area, and about 60-70% of super built-up area, is carpet. So a home sold as super built-up gives you noticeably less usable space than the headline number - that gap is the loading factor.
Does super built-up area include car parking?+
It can include a share of common amenities - lobbies, staircases, lifts, clubhouse and corridors - loaded onto your unit, and some builders add more than others. Covered/stilt car parking is usually charged separately; always ask exactly what the loading covers.
What's the difference between carpet area and saleable area?+
Carpet area is the usable space inside your flat (RERA's pricing basis). Saleable (super built-up) area is carpet plus your share of common areas - the figure builders traditionally quoted. The difference, as a percentage of carpet, is the loading factor.
How do I calculate carpet area from super built-up area?+
Divide the super built-up area by (1 + loading factor). For example, a 1,200 sq ft super built-up flat at 40% loading gives roughly 1,200 / 1.40 = about 857 sq ft of carpet. Use the calculator above to try your own numbers.
What is a good loading factor in Bengaluru?+
Budget and mid-segment projects typically load around 25-30%; amenity-heavy premium projects run 30-38% or more, and the city average has drifted toward the high 30s-low 40s. Lower loading means more usable space for the same price - compare it before you buy.
Is carpet area or super built-up area used for pricing under RERA?+
Carpet area. Since RERA, promoters must disclose and transact on carpet area in advertisements, the agreement for sale and registration. Super built-up is a marketing figure; the legally meaningful number is carpet area.
What is RERA carpet area vs actual carpet area?+
They should match. 'RERA carpet area' is the carpet area the builder registered on the RERA portal using the statutory definition; 'actual carpet area' is what you measure on handover. If they differ materially, that's a red flag - which is exactly why you verify the registered figure before you pay.
- The Real Estate (Regulation and Development) Act, 2016 — carpet-area definition, Section 2(k) (India Code, Govt. of India).
- Karnataka RERA portal — verify a project's registered carpet area.
- ANAROCK research — loading-factor and market data (indicative).
- BricksGuru: free RERA check · A-Khata vs B-Khata · home-buying checklist
Loading ranges and figures are indicative as of 2026 and vary by project; verify the registered carpet area and current price on the Karnataka RERA portal before you decide. General information, not legal or financial advice.
Bipasha Das writes about Bengaluru's property market, the home-buying process and legal due diligence, turning complex property decisions into clear, practical steps for first-time buyers and NRI investors.
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