How to calculate it
Multiply room length by width, add a cutting allowance, then divide by the coverage listed on the flooring carton. Always round up to a complete box.
Worked example
A 15 × 12 ft room is 180 sq ft. With 10% extra, plan for 198 sq ft. If a box covers 20 sq ft, you need 10 boxes (200 sq ft purchased).
Before you order
- Measure closets and adjoining spaces separately, then add their areas.
- Herringbone, diagonal installation, odd angles and many alcoves usually create more offcuts.
- Check whether cartons can be returned and whether the product could be discontinued.
Frequently asked questions
What flooring waste percentage should I use?
Ten percent is a practical starting point for a straightforward rectangular room; complex layouts may need more. Ask your installer or manufacturer about their layout.
Why does it round boxes up?
Flooring is commonly sold by full carton, and a partial box generally cannot be ordered.
Does the price include underlayment or labour?
No. The price field covers flooring cartons only. Add other project expenses in the project dashboard.
Sources & assumptions
Geometry-based estimate. Your product specifications and supplier instructions take priority.
Calculator formulas and explanations prepared for RenovationBinder, 2026-10-15.