How many tiles or how much flooring do you need?
Quick answer: Measure the area in square metres, add extra for cuts (about 10% for tiles laid straight, 15% diagonally and 18% in herringbone; about 7%, 12% and 15% for flooring planks), then divide by the coverage per box and round up to whole boxes.
Ordering tiles or flooring is simple arithmetic with one catch: you always need more than the area of the room, because some pieces are cut and some are wasted. How much more depends on the pattern. Buy too little and the next batch may not match. Buy far too much and you are storing boxes for years.
Measure the area
For a rectangular floor, multiply the length by the width in metres. For an L-shaped room, split it into rectangles, work out each one and add them together. For a wall, multiply its width by the height you are tiling to, then take off doors and windows. Measure to the nearest centimetre and write the figures down as you go.
Add extra for cuts and waste
The pattern decides how many cut pieces you end up with. These are the allowances Tantoo uses:
| Laying pattern | Tiles | Flooring planks |
|---|---|---|
| Straight | 10% | 7% |
| Diagonal | 15% | 12% |
| Herringbone | 18% | 15% |
Add a little more for a small or awkward room with lots of corners, and for large-format tiles, where one broken tile is a bigger share of the job.
Round up to boxes
Tiles and flooring are sold in boxes that cover a stated area. Divide your total area, including the extra, by the coverage on one box and round up. For example: a 3.2 × 2.5 m kitchen floor is 8 m². With 10% for straight tiling that becomes 8.8 m². With boxes covering 1.44 m², 8.8 ÷ 1.44 = 6.1, so buy 7 boxes.
Keep a few spare
Tiles are made in batches, and colours vary slightly from one batch to the next. Check that every box has the same batch number, and keep a few spare tiles or a part pack of flooring after the job. If a tile cracks in five years' time, you will be glad of a perfect match.
Grout, adhesive and underlay
Adhesive and grout are sold by the area they cover, which depends on the tile size, the gap and the trowel. Check the coverage figures on the bags rather than guessing. Floating floors such as laminate need underlay for the whole area, and an expansion gap around the edges, usually around 8 to 10 mm. The maker's instructions give the exact figure for your product.
Read next
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Tantoo is a trading name of Third Coffee Studio Ltd, registered in England and Wales, company number 17517422.