How much waste should I add for flooring?

Add 5–10% for a straight lay, and up to 15% for diagonal or herringbone patterns, where cuts are more frequent.

Do I include doorways and closets?

Include any area the flooring will actually cover, such as thresholds and closet floors where it runs through; leave out spaces it won't reach.

Why buy from the same batch?

Colour and finish can vary slightly between production batches, so boards added later from a different batch may not match your floor.

How Much Flooring Do You Need? (With Waste)

Published 10/16/2025 · 3 min read · Everyday calculators

Marco Bianchi — Home, DIY & motoring writer at Allin

Renovation · Materials

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In short

Divide the room's area by the coverage of one pack of flooring, then add 5–10% for cuts and waste. A 20 m² room with packs covering 2.2 m² each needs 20 ÷ 2.2 = 10 packs, plus 10% ≈ 11 packs. Add more — up to 15% — for diagonal or herringbone layouts, and always round up to whole packs.

A bare room with laminate flooring and a television on a low unit. — Max Vakhtbovych · Pexels · Pexels

Divide the room's area by a pack's coverage, then add for cuts and waste. Here's the method, with an example and how much extra to buy.

Measure the area

Multiply length by width for a rectangular room: a 5 × 4 m floor is 20 m². For an L-shaped or irregular room, split it into rectangles, work out each area, and add them together. Measure to the walls you will actually cover, and include doorways or closets if the flooring runs into them.

Divide by pack coverage

Flooring is sold by the pack, each covering a stated area printed on the label — laminate packs often around 2 to 2.5 m². Divide your room area by that figure: 20 m² at 2.2 m² per pack is about 9.1 packs. Boards within a pack can be trimmed and reused across rows, which is why the base count works before you add waste.

Add for cuts and waste

Rows rarely end on a full board, so you cut and lose offcuts, and the first and last rows need trimming. Add 5–10% for a simple straight layout and up to 15% for diagonal or herringbone, where cuts are more frequent and angled. Small or busy rooms with many doorways and alcoves sit at the higher end.

Buy whole packs, keep a spare

Round your final figure up to whole packs, since you can only buy complete ones — that 9.1 plus 10% becomes 11. Take them from one batch so colour and finish match, and keep an unopened pack afterwards. If a board is scratched or a plumbing repair lifts a section years later, a matching spare turns a headache into a quick fix.

Worked with our own calculator

Flooring calculator

Given

Surface area (m²): 23
Pack coverage (m²): 1.1
Waste (%): 4

Result

Packs needed: 22
Area with waste (m²): 23.92

These figures are produced by the calculator below, not typed in by hand — they are recomputed whenever the tool changes.

Run it on your own figures →

Frequently asked questions

How much waste should I add for flooring?: Add 5–10% for a straight lay, and up to 15% for diagonal or herringbone patterns, where cuts are more frequent.
Do I include doorways and closets?: Include any area the flooring will actually cover, such as thresholds and closet floors where it runs through; leave out spaces it won't reach.
Why buy from the same batch?: Colour and finish can vary slightly between production batches, so boards added later from a different batch may not match your floor.

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Sources

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