If you take one calculation from this entire site, take this one. Commercial space in Gurgaon is quoted on super area, but your business occupies carpet area, and the difference between them is not a rounding error — on commercial property it commonly runs between 30% and 50%. Two units advertised at the same rate can differ by a fifth in what you actually get to use. Until every quote on your shortlist is converted to cost per usable square foot, you are not comparing them at all.
The three measurements, plainly
Carpet area is the usable floor you can actually put desks or stock on. Built-up area adds the walls. Super area — also called chargeable area — adds a proportionate share of lobbies, lifts, corridors, service ducts and common facilities.
You pay on super area. You operate on carpet area. Every rate you are quoted, and every CAM bill you receive, is calculated on the larger number.
Loading factor is the number to ask for
Loading is the gap between carpet and super area expressed as a percentage. On Indian commercial property it typically runs 30% to 50%, noticeably higher than the 25% to 40% common in residential, because commercial buildings carry more lobby, lift and service provision.
A building at 30% loading and one at 50% are offering materially different products at the same advertised rate. This figure is rarely volunteered and is almost always available if you ask for both area numbers.
The calculation itself
Take the quoted rate per square foot on super area, multiply by the super area to get the actual monthly rent, then divide by the carpet area. That gives you effective rent per usable square foot — the only figure on which two buildings can be honestly compared.
Run it across your whole shortlist before viewing anything. It routinely reorders the list, and it occasionally removes the option everyone had assumed was the front-runner.
CAM compounds the same problem
Common area maintenance is also charged on super area, using the building's total common expenses divided by its total chargeable area. So an inefficient building charges you twice for the same inefficiency: once in rent, again in CAM, every month, for the life of the lease.
This is why a high-loading building with a modest headline rate can end up being the most expensive option on a shortlist — and why the comparison has to include CAM to be meaningful.
What to actually ask for
Request the carpet area and the super area as separate numbers in writing, along with the current CAM rate and how it has changed over the past three years. If a carpet figure is not forthcoming, that reluctance is itself information about the building.
For fitted or plug-and-play space, also establish whether the usable figure is before or after the existing fit-out, since partitions and cabins reduce what you can genuinely deploy.
Where loading is worth paying for
High loading is not automatically bad. Generous lobbies, ample lifts and good common facilities are real amenity, and for a client-facing business they may be exactly what the space is for.
The point is not to minimise loading but to see it. Decide deliberately whether you are buying usable floor or buying presentation — both are legitimate, and only one of them is what most occupiers think they are paying for.