Carpet area refers to the area that is to be covered by a carpet or in simpler terms, it is the area excluding the area occupied by the walls. Carpet area is the actual area that is used in a housing unit and hence excludes the area covered by common areas including the lobby, lift, stairs, shafts, balcony, etc. While selecting a house it is advisable to make decisions based on the carpet area.

Since a lot of cases are filed by customers regarding the misinformation given to them about the carpet area, hence According to laws and regulations set by the government, it is necessary for the builders to disclose the carpet area of each apartment to the developers on the basis of which the cost price of each unit is to be calculated. The area outside the main door is completely excluded in case of carpet area but an area occupied by the walls that serve as partitions within the structure is considered as the part of the carpet area. The carpet area also excludes the floor area of the kitchen and bathrooms inside the flat. All the exclusions are added into the built-up area and the super built-up area.

The built-up area, on the other hand, comes after adding up both the carpet area and the wall area. The wall area taken into consideration refers to the thickness of the inner walls of the unit. In general, the wall area constituting the walls is around 20-25% of the built-up area. The total built-up area also takes into consideration the areas maintained by authorities including balcony, flower beds, bathroom, kitchen, staircase, verandah, ducts, and shafts, etc. This extra area adds up to 10% more of the area. In average, 30% of the built-up area is unusable. Hence in a built-up area, only 70% of the built-up area is usable.  The approximate value of the built-up area is calculated by adding the carpet area and 20% of the carpet area. This gives an approximate value and hence used as a rough idea by the builders and developers.

Considering an example, in standard flats, the carpet area is mentioned to be 1000 square feet. Hence 20% of the carpet area gives 200 square feet and therefore the built-up area is 1200 square feet.  The carpet area and built-up area together comprise into the super built-up area that is useful information for developers. Super Built-up area is a term used by the builders and developers and is a crucial number for them. The super built-up area refers to the total area adding up the built-up area and the common area including the corridor, lobby, lift, clubhouse, shafts, staircase, gym, etc. A unit is charged by the builder on the basis of the super built-up area and hence it is termed as ‘saleable area’. While gathering the super built-up area, a factor that comes into play is called the loading factor. The loading factor is defined as the proportionate share of the common area in the apartment which is calculated by multiplying a factor of 1.25 to the carpet area. This loading factor accounts for an increase of around 20% – 30% of the total saleable area. This extra amount is obtained as a difference between the super built-up area and the carpet area.

Most developers charge their apartment units based on the loading factor. Let us consider an example where the carpet area is around 1000 square feet. If the loading factor is 25% for the apartment, then the super built-up area is calculated to be around 1250 square feet and is the saleable area.