Carpet Area vs Built-up vs Super Built-up Area Calculator
Convert between carpet area, built-up area, and super built-up area for any Indian apartment. Enter carpet area to get super built-up, or reverse-engineer carpet from the super built-up area the builder quoted. Also shows effective price per carpet sqft — the only honest comparison metric.
Area definitions — what each term actually means
| Term | Definition | RERA Status |
|---|---|---|
| Carpet Area | The net usable floor area within the walls of your apartment — what you can actually lay carpet on. Excludes walls, common areas, balcony (counted separately at 50%). RERA mandates disclosure on carpet area basis. | RERA mandated |
| Built-up Area | Carpet area + thickness of all walls (internal + external). Typically 20–25% larger than carpet area. Rarely used in pricing anymore post-RERA. | Optional disclosure |
| Super Built-up Area | Built-up area + your proportionate share of common areas (lobbies, corridors, staircases, gym, clubhouse, security cabin). Typically 30–45% larger than carpet area. Pre-RERA, builders quoted prices on super built-up, inflating the apparent rate per sqft. | Pre-RERA pricing basis |
| RERA Carpet Area | Since RERA 2016, all sale agreements and promotional material must disclose price per carpet sqft. Balcony is counted at 50% in the RERA carpet area calculation. If a builder quotes only super built-up area pricing, they are non-compliant — ask for the RERA registration and the carpet area certificate. | RERA 2016 definition |
Typical loading factors by city
| City | Built-up Loading | Super Built-up Loading | Notes |
|---|---|---|---|
| Mumbai | 25–30% | 40–50% | Highest loading in India; older buildings can reach 50%+ super BUA |
| Bangalore | 20–25% | 30–40% | Wide variance by project size and amenity level |
| Hyderabad | 20–28% | 33–42% | Luxury projects in Kokapet/Gachibowli tend higher |
| Pune | 20–25% | 30–38% | Mid-segment projects typically 30–35% |
| Gurgaon / NCR | 22–28% | 35–45% | Large-format townships push loading higher |
| Chennai | 18–24% | 28–38% | OMR corridor projects typically 30–35% |
Loading factors vary significantly by project size, amenity level, and developer. Always obtain the exact loading factor from the RERA Form-1 of your specific project.
Frequently asked questions
What is carpet area as per RERA?
RERA defines carpet area as "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 including the area covered by the internal partition walls of the apartment." Balcony/verandah is disclosed separately and counted at 100% of its area in RERA registrations (not 50% as some builders say).
What is the difference between built-up area and super built-up area?
Built-up area = carpet area + wall thickness (adds ~20–25%). Super built-up area = built-up area + your proportionate share of all common areas (lobby, corridors, staircases, amenity areas) — adds another 10–20% on top of built-up. A 1,000 sqft carpet area flat might have 1,250 sqft built-up and 1,400 sqft super built-up.
Why do builders still quote super built-up area?
Pre-RERA, quoting ₹6,000/sqft on super built-up sounded cheaper than the equivalent ₹8,400/sqft on carpet area. RERA 2016 mandates carpet area pricing, but some builders still show super built-up in brochures alongside the RERA-compliant carpet area figure. Always anchor to the carpet area and its RERA-certified number.
What is a typical loading factor in Bangalore vs Mumbai?
Bangalore: super built-up area typically 30–40% more than carpet area. Mumbai: 40–50% more — the highest in India, partly because older buildings allocated large common lobbies and lifts. A smaller loading factor (say 28–30%) means you get more carpet area per rupee spent — look for this when comparing projects.
How do I calculate the effective price per sqft?
Use the calculator above with Mode A. Enter your carpet area, your project's loading factors (ask the builder's RERA form), and total price. The calculator will show you price per carpet sqft (the economically meaningful number) vs price per super built-up sqft (the marketing number). Always compare projects on carpet area price per sqft.
Can a builder change carpet area after RERA registration?
No unilaterally. Under RERA Section 14, a builder cannot make changes to the approved plans or specifications without two-thirds written consent of allottees. A reduction in carpet area is a breach of the sale agreement. You are entitled to a refund or price reduction proportional to the shortfall. Always measure your flat before final payment.
What is a typical floor rise per floor in Indian projects?
Floor rise (premium for higher floors) typically ranges from ₹50–200 per sqft per floor in mid-segment projects, and ₹200–500/sqft per floor in premium projects. Premium floors add 10–30% to the base price by possession floor. Always check floor-wise pricing in the RERA schedule of payment.
Is balcony area included in carpet area under RERA?
Balcony is NOT included in the standard RERA carpet area. RERA defines carpet area as excluding exclusive balcony/verandah area. However, balcony area must be separately disclosed in the RERA registration and sale agreement. Some builders price balcony at 25–50% of the per-sqft rate. Verify the balcony area and its pricing in your specific allotment letter.