Carpet Area Calculator (RERA) — Built-up & Super Built-up
Carpet area as RERA defines it — and what the builder’s super area really means.
Rooms — inside sizes
Walls and shafts
Exclusive balconies, verandahs and terraces
Super built-up area and price
How the areas add up
| Item | m² | sq ft |
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For general information only, not legal advice. Templates are generic starting points — have a qualified lawyer review anything you rely on.
About the Carpet Area Calculator (RERA) — Built-up & Super Built-up
Find the carpet area of a flat exactly as the Real Estate (Regulation and Development) Act, 2016 defines it: the net usable floor area inside the flat, including the area under the internal partition walls but excluding the external walls, service shafts, exclusive balconies and verandahs, and exclusive open terraces. Enter each room’s inside length and width, the internal walls and any balconies, and the calculator adds them up the RERA way.
It then works out the built-up area (carpet plus the external walls, and balconies if you count them) and the super built-up area from the builder’s loading for common areas — or takes the super area from the brochure and shows the loading it implies. The loading factor and the price per sq ft on carpet, built-up and super built-up area make two offers comparable.
How to use it
- Measure each room wall to wall (or take the inside sizes from the floor plan) and add it with its length and width. Use How many for identical rooms such as two toilets.
- Enter the total length of the internal partition walls and their thickness — RERA counts the floor under them as carpet. Subtract any service shafts or ducts that lie inside your room measurements.
- Add exclusive balconies, verandahs and open terraces: they are listed separately and are not carpet area.
- Enter the external walls and the builder’s loading %, or the super built-up area quoted in the brochure, and the price — then compare the price per sq ft on each basis.
Examples
Rooms 56.58 m² + internal walls 22 m × 115 mm = 2.53 m² → carpet area 59.11 m² (636.25 sq ft); balcony 4.5 m² listed separately
Built-up 71.43 m²; super built-up 92.86 m² (999.53 sq ft); loading factor 1.571 — carpet is 63.7 % of the super area
₹11,788 per sq ft of carpet area, but ₹7,504 per sq ft of super built-up area
Carpet area = 1,300 ÷ 1.30 = 1,000 sq ft
Common uses
- Checking the carpet area in a builder’s agreement against your own measurements.
- Turning a brochure’s super built-up area into the carpet area you actually get.
- Comparing flats from different builders on the price per sq ft of carpet area.
- Working out the usable area of a resale flat from its floor plan.
Carpet area in the RERA Act
Section 2(k) of the Real Estate (Regulation and Development) Act, 2016: “carpet area” means 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.
The Explanation to the clause defines an exclusive balcony or verandah, and an exclusive open terrace, as one appurtenant to the net usable floor area of an apartment, meant for the exclusive use of the allottee. When a promoter registers a project, section 4(2)(h) requires the number, type and the carpet area of apartments for sale in the project along with the area of the exclusive balcony or verandah areas and the exclusive open terrace areas — which is why the calculator keeps balconies and terraces apart from carpet area.
What counts
- In carpet area: the floor of every room, kitchen, toilet and passage inside the flat, and the floor under the internal partition walls.
- Not in carpet area: external walls, service shafts and ducts, exclusive balconies and verandahs, exclusive open terraces.
- Built-up area (a trade term, not defined in the Act): here carpet area + shafts + the external walls, plus balconies and terraces if you tick the box. Some builders count only half of a wall shared with the next flat — enter the wall length that matches the offer you are checking.
- Super built-up area (also a trade term): built-up area plus a share of lobbies, staircases, lifts, clubhouse and other common areas, usually quoted as a loading %.
Loading and comparing prices
The loading factor is super built-up area ÷ carpet area. A flat of 1,000 sq ft carpet sold as 1,350 sq ft super area has a loading factor of 1.35 — 35 % loading on carpet — and only about 74 % of what you pay for is inside your walls. To compare two flats, compare the price per sq ft of carpet area: a lower price per super sq ft can still cost more per usable sq ft.
Measuring tips
Measure each room at floor level from wall finish to wall finish, in two places if the walls are not square, and split L-shaped rooms into rectangles. For the internal walls, add up the length of every partition inside the flat once and take the thickness from the plan or at a door opening. Include toilets, the kitchen, passages and store rooms; leave out shafts, balconies and terraces, which have their own fields.
Source
The Real Estate (Regulation and Development) Act, 2016, Act No. 16 of 2016, Gazette of India (Extraordinary) — sections 2(k) and 4(2)(h); copy published by the Uttar Pradesh Real Estate Regulatory Authority.
Limitations
- Built-up and super built-up area are conventions that vary between builders and states; the calculator shows how they are built up so you can match an offer, but only carpet area has a legal definition.
- State RERA rules and your agreement for sale may add their own rules on how areas are measured and stated.
- Not legal advice. Before signing, check the carpet area stated in the RERA registration of the project and in the agreement for sale, and have a lawyer review the agreement.
Privacy
Everything happens in your browser. What you enter or open here is not uploaded or stored by MySmartCoPilot.
Frequently asked questions
What is carpet area under RERA?
The net usable floor area of the apartment — the floor inside the flat including the area under the internal partition walls — excluding the external walls, service shafts, exclusive balconies or verandahs and exclusive open terraces (RERA Act 2016, s. 2(k)).
Is the balcony included in carpet area?
No. An exclusive balcony or verandah, and an exclusive open terrace, are excluded from carpet area. A promoter has to state their areas separately, next to the carpet area (s. 4(2)(h)).
Are internal walls part of carpet area?
Yes. RERA carpet area includes the area covered by the internal partition walls of the apartment, so a room-by-room total needs the partition walls added: total wall length × wall thickness.
How do I convert super built-up area to carpet area?
Divide by 1 + the loading on carpet: a 1,300 sq ft super area with 30 % loading on carpet is 1,300 ÷ 1.30 = 1,000 sq ft of carpet. If the loading is quoted on built-up area, take off the loading first and then the walls (and balconies, if they were counted).
What is a good loading factor?
The RERA Act does not define loading or super built-up area — only carpet area. Loading depends on how much common space a project has, so compare flats on the price per sq ft of carpet area rather than on the loading alone.
What is the difference between carpet, built-up and super built-up area?
Carpet area is the usable floor inside the flat (defined in RERA). Built-up area adds the external walls and often the balconies. Super built-up area adds a share of the building’s common areas on top of that.