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Formula used
pieces = ⌈((2 × (length + width) − openings) × (1 + allowance/100)) ÷ piece length⌉02
Worked example
A 5 × 4 m room has an 18 m perimeter. Deducting a 0.80 m doorway leaves 17.20 m. With a 10% allowance and 60 cm pieces, 32 pieces are needed.
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Common mistakes
- Using room area instead of perimeter.
- Not deducting doors or cupboard fronts without skirting.
- Forgetting cuts, corners and damaged pieces.
- Confusing the skirting height with its useful length.
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