Skirting Board Length Calculator

Work out skirting board length instantly with clear inputs, formula shown and shareable results.

About Skirting Board Length Calculator

Skirting length is the room perimeter minus doorway openings, plus a wastage allowance for mitres and scribes. Ten percent is realistic because every internal corner needs a scribed cut and every external corner a mitre, both of which produce offcuts.

Formula

Skirting length

length = (perimeter - doorway widths) x (1 + wastage)

Worked example

With the default values below, Skirting Board Length Calculator returns Skirting required of 17.38. Change any input above and every figure here is recalculated in your browser.

Inputs used

Room perimeter: 17.6 m
Doorway openings: 2 doorways
Width per doorway: 0.9 m
Cutting wastage: 10 %

Results

Skirting required: 17.38 m
3 m boards required: 6 boards
Net length after doorways: 15.80 m
Waste allowance: 1.58 m

Step by step

1Values used
2Skirting length
3Skirting required= 17.38 m
43 m boards required= 6 boards
5Net length after doorways= 15.80 m
6Waste allowance= 1.58 m

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why is 10% wastage needed?

Mitres and scribes waste the end of each length, and boards come in fixed sizes so the last piece of each wall leaves an offcut too short to use.

Should I buy in longer lengths?

Yes where possible. Fewer joins on long walls looks far better, and 4-5 m lengths reduce both waste and visible joints.