How to calculate tiles without wasting money. Tiling projects often become expensive when tiles are under-ordered or excessive waste is created through poor planning. This UK-focused guide shows you how to calculate the correct number of tiles properly, allowing for cuts, patterns and realistic wastage.
What you will need
A tape measure or laser measurer. Tile size (length × width in millimetres) Calculator or tile calculator tool. Waste percentage (recommended 10–15%)
Step 1- Measure the Room correctly
Measure the room length and width at the widest points in metres. Example: Room length = 4.0m. Room width = 3.2m. Multiply to get the total floor area: 4.0 × 3.2 = 12.8m²
Step 2- confirm your tile size
Tiles are usually measured in millimetres, such as: 600 × 600mm. 300 × 600mm. 200 × 200mm. Always check the box or manufacturer’s website for the exact tile size.
Step 3- Convert Tile Size to Square metres
To find the tile area in square metres: Example for 600 × 600mm tile: 0.6 × 0.6 = 0.36m² per tile. Then calculate: 1 ÷ 0.36 = 2.78 tiles per m²
Step 4- calculate tiles needed ( no waste yet)
Multiply: Room area × Tiles per m² 12.8 × 2.78 = 36 tiles. This is the theoretical minimum and does NOT include waste.
Step 5- Add Waste allowance
Recommended UK wastage: Straight laying: 10% Diagonal or patterned laying: 15% 36 × 1.10 = 39.6 tiles. Always round UP, so you would order 40 tiles.
Step 6- Use the Tile Calculator
Instead of doing all this manually, to calculate tiles needed, you can simply: Enter your room size. Enter your tile dimensions. Select your waste. Tiling projects often become expensive when tiles are under-ordered or excessive waste is created through poor planning. This UK-focused guide shows you how to calculate the correct number of tiles properly, allowing for cuts, patterns and realistic wastage.
Common Tile Calculation mistakes
Forgetting waste allowance. Measuring only one side of an uneven room. Using approximate tile sizes. Rounding tile quantities down. Not allowing for border cuts, can all lead to wasting money.
Final tip
Tiles are often from specific batches. Ordering too few can mean colour mismatch later. It is always safer to order slightly more than you think you need and not waste money.
You can also try our carpet calculator, paint calculator, plywood Calculator, tile calculator and plank flooring calculator for your projects.
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