How the flooring calculation works
Room area = length × width. Order area = room area × (1 + waste percentage ÷ 100).
Worked example
A 5 m × 4 m room is 20 m². With a 10% allowance, plan to order about 22 m². If each box covers 2.2 m², that is 10 boxes.
Guide: using this calculator accurately
For the full explanation, worked examples, measurement tips and FAQs, read the Flooring Guide →.
How to measure a room for flooring
Measure the longest length and widest width of a simple rectangular room. For L-shaped or irregular rooms, split the space into rectangles, calculate each area, and add them together.
How much flooring waste should I allow?
A waste allowance covers cuts, damaged pieces, pattern matching and off-cuts. A simple rectangular room may need less than a complicated room with many corners or a directional pattern. Follow the flooring manufacturer’s recommendation.
Why box coverage matters
Flooring is often sold by the box rather than by individual square metres. Divide your required order area by the box coverage and round up to a whole box.
What about hallways and multiple rooms?
Calculate each distinct area separately when the direction, pattern or material changes. Keeping a room-by-room measurement list makes ordering and installation planning easier.
Common flooring mistakes
Do not measure only the visible central area. Include alcoves and usable floor sections, account for thresholds and check whether the product requires a particular installation direction.
Frequently asked questions
How much extra flooring should I buy?
There is no single allowance for every project. Use the product or installer recommendation and increase it for complex layouts, diagonal installation or patterns that require matching.
Should I round up boxes?
Yes. Boxes are sold as whole packages, so always round the box count up.
Can I use this calculator for carpet?
The area calculation is useful for estimating square metres, but carpet installation has seams, roll widths and layout considerations that may require a more detailed plan.