Waste allowances by material
The percentage to add to the net area before ordering. Underestimated, it costs a second delivery; overestimated, it sleeps in the back of the van.
| Case | Usual value |
|---|---|
| Tiles, straight lay | 5 to 10 % |
| Tiles, diagonal lay | 15 to 20 % |
| Tiles, chevron lay | 20 to 25 % |
| Large-format tiles | 10 to 15 % |
| Floating wood floor | 5 to 8 % |
| Patterned wood floor, herringbone | 10 to 15 % |
| Paint, walls and ceilings | 5 % |
| Plasterboard | 10 % |
| Insulation, roll or board | 5 to 10 % |
| Broadloom carpet | 10 to 15 % |
Usual sizing values, aligned with this site's calculators. They replace neither a product datasheet nor a regulatory text.
These values cover cutting and breakage, not rework. On a refurbishment with non-parallel walls, always take the top of the range: waste does not depend on the material, it depends on the room's geometry.
The diagonal and chevron rows reuse exactly the multipliers from this site's tile calculator, plus the usual cutting waste. One figure, one source.
To apply these values to a real area, with no account:
Tile calculatorFrequently asked questions
Do you apply the allowance to gross or net area?
On the net area, the one you actually lay. Applying the allowance to an already inflated area counts it twice, which shows immediately on a large floor and never on a bathroom.
Why does diagonal laying cost more?
Because every row meets the walls with a cut instead of ending on a whole tile. The extra cost is double: more material lost, and more cutting time, which often weighs more than the material.
The areas themselves come out of the drawing
An allowance is useless without the area to apply it to. FloorScan reads it off the PDF and exports it to your spreadsheet.