Built-up area and super built-up area is generally used in real-estate. It is used to calculate the cost of property per square feet or square meter.

The built-up area is the carpet area plus the thickness of the outer walls and the balcony. The Super built-up area is the built-up area plus a proportionate area of common areas such as the lobby, lifts shaft, stairs, etc. Sometimes it may also include the common areas such, swimming pool, garden, clubhouse, etc.

The carpet area is the covered area of the usable spaces of rooms in the building. It is measured between walls to walls within the building and is the sum of the actual areas of the rooms where you can carpet.

Now, when the total cost of construction of a building including the cost of land or plot, is lets say, USD 10,000 and its carpet area is 1000 sqft, built-up area is 1250 sqft and super built-up area is 1500 sqft, then the cost of the building per square feet can be calculated as:

Cost per sqft of carpet area = USD 100,000/1000 = USD 100

Cost per sqft of built-up area = USD 100,000/1250 = USD 80

Cost per sqft of super built-up area = USD 100,000/1250 = USD 66.67

In this way, you can arrive at the actual cost of construction per square feet including the cost of land or plot. This can also be used to calculate the selling cost of the property.