How Many Tiles Do I Need? A Simple Room-by-Room Guide for UK DIYers

For walls, treat each wall as a separate rectangle. Measure its height and width, multiply them together, and add the totals. Subtract any large fixtures — a window, a doorway, a built-in cupboard — if they cover a significant portion of wall.

For a kitchen splashback or a small feature panel, the same rule applies: measure the height of the area you want to tile and multiply it by the width. Even small areas benefit from a proper calculation, because tiles are often sold in packs that cover a fixed m² and you want to avoid buying an unnecessary extra pack. Once you have your total m², our free tile calculator can convert that into a specific number of tiles based on the tile size you have chosen — it does the division and rounds up automatically.

These are industry rules of thumb, not guaranteed figures — the exact amount of waste depends on the skill of your tiler, the shape of the room, and the size of the tiles. But they are the starting point every experienced UK tiler uses. It is also worth keeping a small supply of tiles back after the job is finished: if a tile cracks in a year or two, having a spare from the same batch (same dye lot) makes a repair far simpler.

• Straight lay (standard grid pattern): add 10% on top of your calculated m²
• Diagonal or herringbone pattern: add 15–20% because these patterns generate far more cuts, particularly at the edges and corners of a room

This is an illustrative example only, using simple round-number dimensions. Your bathroom will have its own measurements, and your tile size may differ — which is exactly why using the calculator with your own numbers gives you the most accurate result. Results are estimates only — always verify tile quantities with your tile supplier before ordering.

If you are also planning new flooring in adjoining rooms, our flooring calculator works in the same straightforward way. You can find all our home planning tools in the home tools hub.

Q: How many tiles per m² UK? A: It depends entirely on the size of the tile. A 60 cm × 60 cm tile covers 0.36 m², so you need roughly 2.8 tiles per m². A smaller 20 cm × 20 cm tile covers 0.04 m², meaning you need 25 tiles per m². The tile calculator handles this conversion automatically once you enter your tile dimensions.

Q: What wastage allowance should I add when ordering tiles in the UK? A: Most UK tile retailers and trade bodies recommend adding 10% for a standard straight lay and 15–20% for diagonal or herringbone patterns. These are widely used trade rules of thumb; your actual wastage may vary depending on the room shape and the complexity of the cuts involved.

Q: How do I work out how many tiles I need for a kitchen splashback? A: Measure the height and width of the splashback area in metres and multiply them together to get the m² figure. Add 10% for wastage, then divide by the size of a single tile. If the splashback sits between two fitted units with awkward angles, consider adding a slightly higher allowance for additional cuts.

Q: Is it better to order too many or too few tiles? A: Always err slightly on the side of ordering more. If you run short mid-job, a new delivery may come from a different batch with a slightly different shade — this is a real risk with natural stone, porcelain, and hand-made tiles. Having a few spares also means you can repair a cracked tile in future without hunting for a match.