About this calculator
Calculate floor area and order quantity with waste allowance.
For several rooms, calculate each area then add them.
Formula
Order area = length × width × (1 + waste%).
Example
4m × 3m with 10% waste = 13.2m² to order.
Accuracy
NUMTX shows the assumptions next to the calculation so you can replace defaults with values that match your situation. For measurements, supplier rates, fees, interest, tax or regulated work, confirm important figures with the appropriate official or professional source.