Flooring calculator
Work out how much flooring you need for a room. Enter the size and the pack coverage and this calculator gives you the square metres to buy, the number of packs and the underlay.
Flooring calculator
Enter your measurements in metres. Everything updates as you type, and nothing is sent anywhere.
The calculator adds a fixed 10% for cuts and waste, then rounds up to whole packs. Enter the coverage printed on your chosen pack. Awkward shapes and diagonal or herringbone layouts may need a higher allowance checked separately. Underlay uses an assumed 15 m² per roll; verify the actual product coverage and whether underlay is required.
Worked example: packs for a 4 m by 5 m room
The floor is 20 m². Adding the calculator’s 10% cutting allowance gives 22 m². If your chosen pack covers 2.2 m², that is 10 packs. If it covers 2.1 m², 22 ÷ 2.1 is about 10.48, so round up to 11 packs, covering 23.1 m².
For an L-shaped room, split the plan into non-overlapping rectangles and add their areas. Do not count the corner twice. Check the manufacturer’s waste allowance for your laying pattern; the calculator’s fixed 10% does not automatically increase for herringbone.
Underlay is a separate product choice. The tool assumes 15 m² per roll, which may differ from yours, and some flooring already has an attached backing or needs a specific installation system. Confirm suitability before ordering.
Common questions
How much flooring do I need?
Measure the length by the width of the room for the area, and add about 10% for cuts and waste. Buy by the pack, since flooring is sold in packs that each cover a set area, usually printed on the label. The calculator turns your room size into packs.
How much extra flooring should I order?
About 10% extra for a straight lay in a simple room, and up to 15% for a diagonal or herringbone pattern or a room with lots of alcoves and doorways. It is worth keeping a spare pack in case of damage later.
These quantities are a guide to help you order. Always round up and check with your supplier before buying.