Tiles are one of the few materials where under-ordering doesn't just mean a second trip to the shop — it can mean a visible colour mismatch that's permanent.
Tiles are manufactured in batches, and even the same product code can shift slightly in shade between production runs — the "dye lot." A box bought this year and a box of the identical tile bought next year, from the same range, aren't guaranteed to match under close inspection. Buy everything for a job from a single batch, and the spare box you keep afterwards is guaranteed to match if you ever need a repair.
| Layout | Typical waste allowance |
|---|---|
| Straight grid | 10% |
| Diagonal | 15% |
| Herringbone / complex pattern | 20% |
A 12 m² room with 300×300mm tiles at 10% waste needs 147 tiles — 14 full boxes at 11/box, 7 tiles more than the strict minimum. That surplus isn't padding; it's cuts, breakages, and the buffer that makes a straight-grid job actually finishable without a mid-job supplier trip.
Enter your area and tile size for the precise number needed, plus full boxes to buy.
Use the Tile Calculator →