Built-up area / Plinth Area is the entire area occupied by the apartment, including the area occupied by the internal and external walls of the apartment. Super Built-up Area is the Built-up Area plus the proportional share of the common areas like corridors, lift wells, staircase, community halls, security/servant quarters, etc. Super Built-Up Area is therefore only applicable for apartment communities or multi-dwelling units. Average size of 1 BHK should be 400 to 700 sqft, 2BHK-800 to 1300 sqft, 3 BHK-900 to 3000 sqft. Average area for kitchen should be 400 sqft and toilet also somewhat the same.