Built-up area is the total area of your apartment unit measured from the outer edges of the external walls. It includes the carpet area (usable space), plus the area occupied by internal walls, external walls, columns within the apartment, and attached balconies or terraces.
Built-Up Area = Carpet Area + Wall Area + Balcony Area
Built-up area sits between carpet area and super built-up area in terms of size. It gives you a better picture of the actual physical footprint of your apartment than carpet area alone, but does not include any share of common areas.
Typical breakdown: - Carpet area: ~80-85% of built-up area - Walls and columns: ~10-15% of built-up area - Balconies: ~5-10% of built-up area
Understanding built-up area helps you assess the overall design efficiency of an apartment. A unit with thick walls or many columns will have a lower carpet-to-built-up ratio.