About this calculator
Linear length and stock pieces of skirting board, dado or coving for one or more rooms, with doorways deducted.
How it’s calculated
Run = room perimeter − doorway widths. Pieces = run × (1 + waste) ÷ stock length.
Worked example
With these inputs:
- Room length
- 4.2 m
- Room width
- 3.6 m
- Number of identical rooms
- 1
- Doorways (per room)
- 1
- Doorway width
- 900 mm
- Stock length
- 4.2 m
- Waste allowance
- 15%
the result is:
- Trim needed
- 16.9 lin m
- Net run
- 14.7 lin m
- Inside corners (per room)
- 4
Tips from the trade
- Buy the longest lengths you can handle. Fewer joins look better.
- 15% waste covers mitres and short offcuts. Use 20% in rooms with lots of corners.
- Cope the inside corners rather than mitring them. Coped joints stay tight as the house moves.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and the Building Regulations before ordering.