Carpet Area vs Built-up vs Super Built-up Calculator
Builders quote super built-up area, but you live in the carpet area. The gap is often 25–40%. See all three figures and the true per-sq-ft price.
Carpet area
696
- Built-up area
- 800
- Super built-up area
- 1,000
- Carpet as % of super built-up
- 69.6%
Formula
Built-up = Carpet × (1 + wall loading). Super built-up = Built-up × (1 + common area loading). Real price per carpet sq ft = Quoted price × Super built-up ÷ Carpet.
Worked example
A 1,000 sq ft super built-up flat with 15% wall and 25% common loading has about 696 sq ft of carpet area. At ₹8,000/sq ft quoted, you really pay ₹11,500 per carpet sq ft.
Assumptions
- RERA requires builders to sell on carpet area, defined as net usable floor area excluding external walls and balconies but including internal walls.
Frequently asked questions
- What is the RERA definition of carpet area?
- Net usable floor area of an apartment, excluding external walls, service shafts, balconies and open terraces, but including the area covered by internal partition walls.
- What is a reasonable loading factor?
- 20–30% between carpet and super built-up is common; above 40% means you are paying heavily for amenities and common spaces.
Last reviewed 2026-10-31. Results are estimates for information only and do not constitute financial, tax or legal advice.