What is built-up area?
Also called: plinth area, BUA, covered area
Built-up area is the carpet area plus the space taken by the flat's walls, and usually its balconies. It tends to run 10 to 20 per cent above the carpet area.
Think of it as the footprint of your flat if you drew a line around the outside of its walls. The inner walls, the outer walls and, in most builders' calculations, the balcony all go in. What doesn't go in is any share of the lobby, lift or staircase; that extra layer is what turns built-up into super built-up.
New projects rarely lead with this figure now, because RERA pushed carpet area to the front. But you'll still meet it constantly. Resale agreements drawn up before 2017 in Bengaluru, Hyderabad and Chennai often describe the flat only by built-up or 'plinth' area. Municipal tax systems use it too: BBMP's property tax in Bengaluru is worked out on built-up area, and in Maharashtra the valuation guidelines that go with the ready reckoner treat built-up area as carpet area multiplied by 1.2 when converting between the two.
There's no single legal definition of built-up area across India, which is the real problem. One builder counts the full balcony, another counts half, a third includes a flower bed. Wall thickness matters as well; a flat with 9-inch brick outer walls will show a noticeably higher built-up figure than an identical layout with thinner block walls, and none of that extra is space you can use.
When a seller quotes built-up area, ask for the carpet area in writing, or measure it. Your bank's valuer will.
A 2010-vintage flat in Koramangala is described in its sale deed as 1,250 sq ft built-up. The buyer's valuer measures 1,040 sq ft of carpet, so the ₹1.9 crore asking price works out to about ₹18,270 per sq ft of usable space.
Some resale sellers describe built-up area as 'carpet' in listings. If the number looks generous for the rooms you've walked through, it probably is.
Questions people ask about built-up area
Is built-up area the same as plinth area?
In everyday use, mostly yes. Government works manuals define plinth area a little more strictly, but builders and sellers in South India use the two terms interchangeably.
Which area is used for stamp duty?
Stamp duty is charged on the agreement value or the government rate for the property, whichever is higher. Where the state rate is per sq m, the valuation rules say which area to apply, and in Maharashtra that's built-up area derived from carpet.