Short answer: Loading is the super built-up area minus the RERA carpet area, divided by the carpet area. A flat quoted at 1,350 sq ft with a 1,000 sq ft carpet area has 35% loading, so you pay 1.35 times the quoted rate for each square foot you can use. RERA sets no loading limit. It defines carpet area and makes builders disclose it.
- Carpet area is the legal measure: section 2(k) of the RERA Act counts the usable floor inside the flat plus internal walls.
- Balconies and terraces are separate: exclusive balconies, verandahs and open terraces are left out of carpet area and listed on their own.
- Super built-up is a sales figure: the Act does not define it and sets no loading limit.
- Loading = (super built-up − carpet) ÷ carpet. Price per sq ft of carpet = quoted rate × super built-up ÷ carpet.
- Check three documents: the RERA project page, the agreement for sale and the cost sheet should show the same carpet area.
Use the calculator to see how much of a quoted "super built-up" area is your flat's carpet area, and what you pay per square foot of floor you can actually use. Type in the figures from your own documents. Nothing you enter leaves your browser.
From the agreement for sale or the RERA project page.
The area on the brochure or cost sheet.
- Loading on carpet area
- –
- Carpet area as a share of super built-up
- –
- Balcony and terrace (yours alone)
- –
- Everything else in the super built-up figure
- –
- Carpet area in the other unit
- –
- Total at the quoted rate
- –
- Same total per unit of carpet area
- –
Estimate only. The calculator does arithmetic on the figures you enter. It does not check them against RERA records or the approved plan.
What the law counts as carpet area
Section 2(k) of the Real Estate (Regulation and Development) Act, 2016 defines carpet area as "the net usable floor area of an apartment, excluding the area covered by the external walls, areas under services shafts, exclusive balcony or verandah area and exclusive open terrace area, but includes the area covered by the internal partition walls of the apartment".
| Part of the flat | In RERA carpet area? |
|---|---|
| Floor inside the flat | Yes |
| Internal partition walls between rooms | Yes |
| External walls | No |
| Service shafts and ducts | No |
| Exclusive balcony or verandah | No. Shown separately |
| Exclusive open terrace | No. Shown separately |
| Lobbies, stairs, lift wells, clubhouse share | No. These are common areas |
"Super built-up area" is not defined in the Act. It is a sales figure. It usually adds walls, balconies and a share of common areas such as lobbies, staircases and amenities to the carpet area. Section 2(n) of the Act lists what counts as common areas.
What the calculator works out
- Loading on carpet area = (super built-up − carpet) ÷ carpet × 100. This is how much the quoted area is "loaded" above the carpet area.
- Carpet share = carpet ÷ super built-up × 100. Some people call this efficiency. It is the same comparison seen the other way.
- Everything else = super built-up − carpet − exclusive balcony − exclusive terrace. That is the external walls, shafts and the common-area share, together.
- Price per unit of carpet area = rate × super built-up ÷ carpet. Use the rate on your own cost sheet.
- Units: 1 square metre = 10.7639 square feet. RERA project pages often give areas in square metres.
A worked example
These are made-up round numbers, not any project's figures. A flat is quoted at 1,350 sq ft super built-up. The RERA page shows 1,000 sq ft carpet area and an 80 sq ft exclusive balcony.
| Line | Working | Result |
|---|---|---|
| Loading on carpet area | (1,350 − 1,000) ÷ 1,000 | 35% |
| Carpet share | 1,000 ÷ 1,350 | 74.1% |
| Everything else | 1,350 − 1,000 − 80 | 270 sq ft |
| Carpet area in square metres | 1,000 ÷ 10.7639 | 92.90 sq m |
| Per sq ft of carpet, at a quoted ₹X per sq ft of super built-up | X × 1,350 ÷ 1,000 | 1.35 × X |
The law sets no standard loading percentage. Compare flats on carpet area and on the total price, not on the super built-up figure.
Where to find the real numbers
The RERA project page
Section 4(2)(h) of the Act requires the promoter to disclose the number, type and carpet area of the apartments for sale, with exclusive balcony, verandah and open terrace areas shown separately. Look the project up on the Karnataka RERA website. Our guide on checking a project on RERA Karnataka shows where.
The agreement for sale
Under section 13(2), the agreement for sale must set out the particulars of the development, including the construction of the apartment and its specifications. Check that the carpet area there matches the RERA page and the unit you were shown.
The brochure and the cost sheet
Ask the sales team to write the carpet area next to every super built-up figure they quote. Section 12 makes the promoter liable for loss caused by a false statement in an advertisement or prospectus, so keep copies.
At possession
Measure room by room, wall to wall, inside the external walls, and add internal partition walls. If the total is clearly short of the agreement, see our answer on what to do when the flat is smaller than the agreement says.
Verify with your lawyer: this page explains the RERA Act's definitions and does arithmetic. It is not legal advice. Before you sign, have your own property lawyer check how the agreement for sale states the carpet area and what it says about any shortfall.
Frequently asked questions
Loading is how much the quoted super built-up area exceeds the RERA carpet area, usually given as a percentage of carpet area. It covers external walls, shafts, balconies and a share of common areas.
Subtract the carpet area from the super built-up area, divide by the carpet area and multiply by 100. For 1,350 sq ft super built-up and 1,000 sq ft carpet, loading is 35%.
The RERA Act does not set a loading percentage. It defines carpet area in section 2(k) and requires carpet area to be disclosed on the project's RERA page under section 4(2)(h).
No. Section 2(k) excludes exclusive balconies, verandahs and open terraces from carpet area. The promoter has to show them separately.
Multiply by 10.7639. So 92.9 sq m is about 1,000 sq ft. The calculator converts the carpet area for you.
Sources
Checked 22 Oct 2026.
- The Real Estate (Regulation and Development) Act, 2016, sections 2(k), 2(n), 4(2)(h), 12 and 13, as hosted by Karnataka RERA: https://rera.karnataka.gov.in/resources/staticpage/Real_Estate_Act.pdf
- Karnataka Real Estate Regulatory Authority, project search: https://rera.karnataka.gov.in/viewAllProjects
- Karnataka RERA FAQs: https://rera.karnataka.gov.in/resources/staticpage/KARNATKA_FAQs.pdf
