Tile wastage: how much extra should you order?
May 2026 · 6 min read
Tile wastage is one of those topics where the standard advice ("add 10%") is right often enough that nobody questions it, and wrong often enough that some renovations come up two boxes short on day three of the install. The right number depends on your lay pattern, tile size, and how much future repair stock you want to keep. Here's how to actually work it out.
Why wastage exists
Three real costs eat into a tile order:
- Cuts.Every tile that runs into a wall, around a vanity, or against a doorway gets cut. The offcut usually can't be reused.
- Breakage. Some tiles arrive cracked from transit. Some break on the saw. Large format and natural stone are more fragile than small porcelain.
- Pattern matching. Marble looks, herringbone, and any vein-matched lay involves rejecting some tiles for orientation or grading.
The baseline: 10%
For a straight lay (stack bond or running bond, brick offset under 50%), small to medium porcelain (under 600×600), in a regular rectangular room, 10% is the right number. So a 25m² floor needs 27.5m² of tile ordered.
Round up to the next full box. Box sizes vary by range: typically 1.0–1.4m² per box for 600×600, smaller for mosaics, larger for herringbone planks. Don't split boxes between rooms if you can avoid it.
When 10% isn't enough
Add another 5% (so 15% total) if:
- Tile is 600×1200 or larger (more cuts proportionally, more breakage).
- Room is irregular: multiple corners, cut-outs around shower niches, columns.
- You're tiling a feature wall with bookmatched veins.
Add another 10% (so 20% total) if:
- Lay pattern is herringbone or chevron: these have inherent waste from the 45° cuts at every wall edge.
- Tile is natural stone (more breakage, more colour grading rejection).
- Diagonal lay (45° to the walls): every perimeter tile is a triangle.
For a herringbone lay in natural stone in an irregular room, yes, that means ordering 25–30% extra. It's not unusual. Tilers will tell you when they survey the job.
Worked examples
Bathroom floor, 600×600 porcelain, straight lay, 8m². Add 10% = 8.8m². Round to next full box. Likely order 9m².
Open-plan living, 600×1200 marble look porcelain, brick offset, 60m². Add 15% = 69m². Likely order 70m² or whatever the next clean box quantity is.
Herringbone hallway, 75×300 timber-look, 12m². Add 20% = 14.4m². Order 15m².
Pool surround, 600×600×20 paver, 30m². Add 15% (perimeter cuts around pool coping) = 34.5m². Order 35m².
Future repair stock
Dye lots between manufacturing batches differ slightly. If you need to replace a cracked tile in three years and the range is still in production, the replacement box almost certainly won't match. The fix is to keep one to two extra boxes from your original order in the garage.
For a feature tile (zellige, terrazzo slab, anything imported in small batches and likely to be discontinued) keep three to five boxes. The extra cost up front is a fraction of the cost of pulling up an entire floor in five years because two tiles cracked and the range is gone.
A simple checklist
- Measure the floor or wall area in m². Don't deduct for shower hobs or skirtings unless they're larger than 0.5m².
- Pick the wastage % from the table above.
- Multiply, round up to the next full box.
- Add one to two boxes for repair stock.
- Confirm batch numbers when ordering: all tiles from the same batch.
- Inspect every box on delivery before the tiler starts. Damaged tiles need to be reported within the supplier's claim window (usually seven days).
Order tiles at Marmoré
Every product page lists box size and m² per box. Talk to us if you're working out a quantity for a tricky room. We work this out for customers every day and would rather you have the right amount than the standard 10%.