What Is RERA Carpet Area and How to Verify It
RERA carpet area is the one number a builder cannot define their own way. Here is what the Act counts, what it leaves out, and how to check the figure yourself from the RERA portal, the agreement and the floor plan.
· 5 min read · 1K views · by the Cortex Digital Hub team
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Before 2016, "carpet area" meant whatever the brochure said it meant. The Real Estate (Regulation and Development) Act gave the term a legal definition and made it the only basis on which a registered project may be sold. That single change is why the number on a RERA project page and the number in a glossy brochure often disagree, and why it is worth knowing how to check the figure yourself before you pay a booking amount.
What RERA carpet area means
Section 2(k) of the Act defines carpet area as the net usable floor area of an apartment. It includes the area covered by the internal partition walls of the apartment. It excludes the area covered by external walls, areas under service shafts, exclusive balcony or verandah area, and exclusive open terrace area. That is how the Act reads; each state RERA applies it through its own rules and forms, so the presentation on the Telangana, Karnataka or Maharashtra portal can vary a little, but the substance does not.
Two details catch buyers out. First, internal walls count. The wall between your bedroom and the living room sits inside the flat, so its footprint is part of your carpet area even though you cannot put a sofa on it. Second, balconies do not count, but they must be declared. A project page will normally show carpet area and exclusive balcony area as two separate numbers. Adding them together gives you something, but it is not RERA carpet area.
How it differs from builder carpet, built-up and super built-up
Before the Act, a brochure's "carpet area" could mean wall-to-wall usable area, or it could quietly fold in the balcony, or half the external wall. Built-up area adds the external walls and balconies on top of that; super built-up adds a loading for lifts, lobbies, corridors, the clubhouse and the gym. The three are compared properly in carpet area vs built-up vs super built-up, so the short version here is enough: RERA carpet area is the only one of the four with a statutory definition, and it is nearly always the smallest number on the page. A 2 BHK sold as 1,100 sq ft super built-up in Hyderabad or Bangalore often has a RERA carpet area between 700 and 780 sq ft, depending on how efficient the tower is.
Verify it on the state RERA website
Every registered project has a public page on its state portal. Search by project name or registration number, open the project details, and look for the unit-wise or typology-wise carpet area the promoter has declared. This is the figure the builder is legally bound to, and it was uploaded with the sanctioned plans, which many portals let you download.
Note three things: the registration number, the date of the last update, and the carpet area for your exact unit type (not just "2 BHK", but the specific type if the project has 2 BHK variants). If the brochure says 1,100 sq ft and the portal says 740 sq ft carpet, nothing is wrong yet; those are different measures. Trouble starts only when the number the sales team calls "carpet" is higher than what the portal shows.
Verify it in the agreement for sale
The agreement for sale under RERA must state the carpet area, and the price is meant to be linked to it. Find the clause, usually in the schedule describing the apartment, and read it next to the portal figure. They should match to the square foot.
Then find the variation clause. The Act allows the carpet area delivered after construction to differ slightly from what was agreed. If the finished flat is smaller, the promoter must refund the difference at the agreed per sq ft rate within the period the state rules specify. If it is larger, the extra you can be charged for is capped, commonly at three percent. A fair agreement spells out both directions. One that only mentions the increase, or is vague on the refund, is worth a question before you sign.
Verify it from the floor plan
This is the check most buyers skip, and it is the only one that does not rely on what the promoter wrote. Take the unit plan from the brochure or the sanctioned drawing. If it is a small brochure crop or a photographed sheet, run it through the free Floor Plan Redraw first so the dimension lines are legible; our guide on how to read a floor plan covers what those lines mean.
Measure each room's internal length and width and multiply, then add the passage, foyer, utility and any store. Next add the internal walls: either total the running length of every wall inside the flat and multiply by its thickness (most apartment partition walls are 4 to 6 inches, or 100 to 150 mm), or take the simpler route and measure the flat's outline to the inside face of the external walls, which gives the same answer. Leave out the balcony, the external wall thickness, and any shaft, duct or AC ledge. Here is what that looks like for a typical 2 BHK:
| Space | Internal size (ft) | Area (sq ft) |
|---|---|---|
| Living and dining | 16 × 12 | 192 |
| Master bedroom | 12 × 11 | 132 |
| Bedroom 2 | 11 × 10 | 110 |
| Kitchen | 10 × 8 | 80 |
| Toilet 1 | 7 × 5 | 35 |
| Toilet 2 | 6 × 4.5 | 27 |
| Passage and foyer | — | 48 |
| Utility | 6 × 4 | 24 |
| Usable floor subtotal | 648 | |
| Internal walls (about 120 running ft × 0.4 ft) | 48 | |
| RERA carpet area | about 696 | |
| Balcony (declared separately, not counted) | 10 × 4 | 40 |
| External walls, shaft (not counted) | — |
If the portal shows 700 sq ft for this unit, the plan and the declaration agree. If it shows 760, something has been counted that should not have been, and you are entitled to ask what. When walls and shafts are hard to tell apart on a flat drawing, a 3D render of the same plan shows the thick external walls, the thin partitions and the duct as solid objects, with the layout kept exactly as drawn.
Red flags to watch for
A sales deck that says "carpet area" without "RERA" in front of it is the first one; ask which definition they mean. A per sq ft rate quoted on super built-up while the carpet figure is "around" something is the second. Watch for balconies silently included in the carpet number, for a portal unit type that does not match the one you are being sold, for a plan with no dimensions at all, and for an agreement that mentions the three percent increase but is silent on refunds. None of these is proof of anything wrong, but each one is a reason to pull the portal page and the plan and do the sum above. The patterns in floor plan mistakes that confuse home buyers overlap with most of them.
Frequently asked questions
Does RERA carpet area include internal walls?
Yes. The Act counts the area under internal partition walls as part of carpet area. It leaves out external walls, service shafts, balconies and open terraces.
Is the balcony part of RERA carpet area?
No. Exclusive balcony or verandah area is excluded from carpet area and must be declared as a separate figure. A builder who adds the two together is not quoting RERA carpet area.
What if the delivered flat is smaller than the carpet area in the agreement?
The agreement should provide for a refund of the shortfall at the agreed per sq ft rate. The exact timeline and the cap on any increase are set by the state rules, so read that clause before you sign.
Where do I find the official carpet area for a project?
On the state RERA portal, under the project's registration page. Search by project name or registration number and look for the unit-wise carpet area the promoter has declared.