Built-Up vs Carpet Area: The Critical Difference
When your builder says your flat is 1200 sqft, that is typically the Super Built-Up Area — which includes your flat's walls, the lift lobby, staircase, and other common areas. The actual area inside your 4 walls (the Carpet Area) is typically only 65-75% of that figure.
For interior design, what matters is the Carpet Area. This determines how much material you need, how many workers are required, and how long the project will take. Always measure your actual carpet area, not the builder-quoted super built-up area.