Tile is the material where 'exactly enough' is a plan to fail. Every layout wastes tile — the only question is whether you budgeted for it or discover it on a Sunday afternoon. This guide sets out honest allowances by layout, and the situations that push any layout higher.
The base allowances by layout
A straight grid in a simple rectangular room: 10 percent. Brick-bond (offset) layouts: 10 to 12 percent. Diagonal layouts at 45 degrees: 15 percent. Herringbone and chevron: 15 to 20 percent, because nearly every edge tile is cut at an angle and the offcut is scrap. Mosaics on mesh sheets waste least — around 7 to 10 percent — but one damaged sheet still needs a spare.
What pushes the number up
Small rooms waste proportionally more than big ones, because the same number of perimeter cuts spreads over less area. Large-format tiles in small rooms are the extreme case: a single cut can consume half a tile. Rooms with alcoves, boxed pipes and multiple doorways add cuts; first-time tilers should add a further 5 percent for the learning curve in the first square metre.
Keep spares after the job
Store at least four to six leftover tiles, flat and dry, with the grout colour noted. Tile ranges are discontinued constantly, and a cracked tile in five years becomes a whole-floor problem without a matching spare. The same logic applies to keeping one unopened bag of the exact grout.
Buying smart
Check every box carries the same batch or calibre number before you start, buy from a store that accepts returns of full unopened boxes, and never begin with the last box of a discontinued clearance line — if the count falls short, there is no more.
Frequently asked questions
Can I return unopened boxes of tile?
Many stores accept full unopened boxes within a returns window, which makes rounding up low-risk. Confirm the policy before ordering, and keep the receipt with the spare tiles.
Does waste differ between floor and wall tiles?
The layout logic is the same, but wall work around sockets, windows and niches adds cuts — budget an extra couple of percent for a heavily featured bathroom wall.