Carpet, built-up and super built-up area calculator

How it works

Carpet area is the floor space inside the walls. Built-up area = carpet area + walls (and balconies, if your builder includes them). Super built-up area = built-up area + your share of common areas such as lobby and stairs. The percentages differ between builders, so type the ones in your agreement.

How to use it

1. Choose which area you know: carpet, built-up or super built-up, and type it.
2. Type the wall percentage and the common-area percentage from your agreement.
3. Read all three areas. Add the price to compare the rate on each.

Worked example

Carpet 1,000 sq ft with walls adding 12% gives built-up 1,120 sq ft. A 25% common-area share on that gives super built-up 1,400 sq ft, so your carpet area is 71.4% of what you pay for. For ₹56,00,000 the rate is ₹4,000 on super built-up but ₹5,600 on carpet.

Common mistakes

• Using a percentage you guessed. Read the figures in your builder's agreement.
• Comparing two projects on super built-up rate alone. Their loading can differ a lot, so compare the carpet rate too.
• Assuming balconies are always in built-up area. Builders and states treat them differently.

Questions people ask