How much extra should I buy for waste?

For a standard straight grid or brick bond layout, add 10% to your tile count. If you are laying herringbone or diagonal tiles (at 45 degrees to the wall), increase that to 15% because those patterns produce more cuts at the edges. For natural stone or large-format porcelain above 600 mm, budget 15% regardless of layout. Keeping a few spare tiles is also useful for future repairs.

Does grout gap size affect how many tiles I need?

Yes. A wider grout gap increases the effective area each tile covers, which means you need slightly fewer tiles overall. The difference is small per tile but adds up across a full room, so always include the grout gap in your calculation.

How do I tile around obstacles like pipes or pillars?

Measure the obstacle and subtract its area from your total floor area, then add a few extra tiles to your waste allowance. Cutting tiles to fit around pipes and corners increases breakage, so budget an extra 5% on top of your usual waste factor.

What tile size is best for small rooms?

Smaller tiles, around 20 cm to 30 cm, generally work better in compact spaces like bathrooms or ensuites. They require fewer awkward cuts along the edges and produce less waste. Larger tiles can make a small room feel bigger visually, but the extra cutting and waste often outweigh that benefit.

How many boxes of tiles do I need?

Most tile boxes cover roughly 1 square metre, though this varies by manufacturer and tile size. Divide your total required area (including waste) by the coverage listed on the box. Always round up to the next full box. You can't buy half a box.

Tile Calculator

Find out exactly how many tiles to buy. Grout gaps and extra for cuts are already factored in.

Room dimensions

Length

Width

Tile size

Tiles (incl. cuts)

145pcs

Room area: 12.00 m²
Tile area (with grout): 918.1 cm²
Tiles (before cuts): 131
Boxes (approx. 1 m² each): 14

Tile Calculator

How tile calculations work

How to measure your space

Tile layout patterns and waste

Common mistakes to avoid

Frequently asked questions

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