How many tiles do I need?
Divide the area you're covering by the area of a single tile, then add a margin for cuts, breakages and future repairs — usually 10%, or more for diagonal layouts and busy rooms. Because tiles are sold in boxes, round the total up to whole boxes so you're never a tile short mid-job.
Frequently asked questions
How much wastage should I allow?
10% is a safe default for straight layouts. Allow 15% for diagonal patterns or rooms with lots of corners and cuts.
My tiles are in inches, not mm.
Multiply inches by 25.4 to get millimetres — a 24-inch tile is 610 mm.
Why keep spare tiles?
Dye lots vary between batches, so a few spares from the same lot make future repairs invisible.