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Formula used
tiles = ⌈(length × width × (1 + allowance/100)) ÷ area of one tile⌉02
Worked example
A 5.20 × 3.60 m room covers 18.72 m². With a 10% allowance, the theoretical order covers 20.59 m². With 60 × 60 cm tiles, 58 tiles are required.
03
Common mistakes
- Mixing tile dimensions in centimetres with room dimensions in metres.
- Adding the allowance after rounding instead of before.
- Failing to deduct areas that will genuinely not be tiled.
- Ordering the result without checking complete boxes, shade and calibre.
04