Skirting Board Calculator

Your measurements

The room

Room length Metres. The longer side of the room. A room that is not a plain rectangle — a chimney breast, a bay — is measured wall by wall and added up.

Room width Metres. The shorter side. Measure along the wall at skirting height, not across the floor, because a wall that is out of square shows up in the last length.

Openings to deduct

Number of doorways How many openings the skirting has to break around — a door, an archway, a serving hatch at floor level. Leave it at 0 for a room with no openings on the run.

Opening width Millimetres of wall each opening takes out of the run. 900 mm is a planning figure for a standard doorway — measure each opening, because an archway is wider.

The board

Board length Millimetres in the length you are buying. 2.4 m and 3 m are the common UK stock lengths, and taller boards often come longer. Check what the merchant actually stocks — the 2,400 mm here is a typical figure, not a promise.

Waste allowance % extra for the cuts. Every corner takes one — a scribe at an internal corner, a mitre at an external — and each opening needs a return. 10% suits a plain room; a bay or a chimney breast wants more.

Results

Fill in every measurement above and your results will appear here.

Your shopping list

Timber is sold in whole lengths, so the figure rounds up. The adhesive and fixing lines are planning estimates only — check the product data and the fixing you actually need.
Material	Quantity	Notes

Room in plan: the skirting band round the inside of the walls, the doorway punched through it, and the room measured length by width. It redraws to your own figures as you fill the form in.

Check current prices

Skirting is quoted by the length, and the price turns on the profile, the material and the height rather than the running metre alone, so compare like with like — a moulder's profile in a softwood length and a foil-wrapped MDF length of the same height are not the same product. Check the stock length against your longest wall, because a run that needs a joint shows the joint for ever, and check whether the profile is a stock line or made to order, because a made-to-order profile cannot be topped up in a hurry.

Wickes
B&Q
Travis Perkins
Jewson
Local timber merchant
Online mouldings supplier

No prices or shop links are shown here. Check today's pack size, coverage and stock with whichever supplier you use — those change more often than the quantities do.

How the skirting board calculator works

Skirting is sold by the length, not by the metre, so the question is not how many metres of board a room takes but how many whole lengths you have to carry home. The calculator starts with the perimeter — twice the length plus twice the width for a plain room — and subtracts the openings the skirting has to break around, such as a doorway or an archway. What is left is the run of wall you actually clad.

Then it adds the waste allowance and divides by the stock length you are buying. A 5 m × 4 m room has 18 m of wall; take off one 900 mm doorway and you have 17.1 m of run; add 10% for the corners and it is 18.81 m; at 2.4 m a length that is 7.84 lengths, so you buy 8. The rounding is the point: you cannot buy 0.84 of a board.

Corners and openings are where the board goes

Every corner takes a cut. An internal corner is usually scribed, which means shaping the end of one board to the profile of the other and cutting away rather more than you would expect; an external corner is a mitre, which is two angled cuts for a single join. Each opening needs a return as well, so the board turns and meets the door casing. A plain rectangular room uses less of each length than a room with a bay, a chimney breast or several doors — which is what the waste allowance is for.

Think about the stock length before you buy. If a wall is longer than the longest board the merchant stocks, the run needs a joint, and a joint in skirting is always visible. On paper it is cheaper to buy shorter boards; in the room, a longer length is usually worth the difference.

Fixing, and what this page does not do

This page works out how much board to order. It does not choose the profile, the height or the material, and it does not size the fixing — the fixing lines in the shopping list are estimates to check against the product data. As a rule, skirting wants mechanical fixings as well as adhesive: the adhesive holds the board to the wall, and the fixings stop a long run springing off. On a plasterboard wall, fix into the studs rather than into the plasterboard alone.

One thing worth knowing: fixing timber skirting is not itself notifiable building work in England. But where the wall is part of a separating wall between dwellings, or forms part of a protected escape route, the wall lining is part of a controlled build-up and what you fix it with can matter — check with your local building control before you alter a lining in a flat. And if the skirting you have in mind is a tiled or masonry type bedded on a mortar bed rather than timber fixed to the wall, that bedding is a mortar job rather than a timber one, and the sand, cement and mortar calculator covers the mixes for it.

Skirting board FAQs

How do I work out how much skirting board I need?

Measure the room's perimeter — 2 × (length + width) for a plain rectangle — then take off the openings where the skirting runs through, such as a doorway, and add a waste allowance for the cuts. A 5 m × 4 m room is 18 m of wall; less one 900 mm doorway that is 17.1 m, and with 10% for the corners it is 18.81 m. At 2.4 m a length that is 7.84 lengths, so you buy 8.

How many lengths of skirting board come in a pack?

Usually one. Skirting is sold by the length — 2.4 m and 3 m lengths are the common UK sizes, and taller boards often come in longer lengths again — because it is timber, not a packed product. That is why the calculator works in whole lengths and rounds up: you cannot buy 0.84 of a board.

Should I deduct the doorways?

Yes. The skirting runs up to the door casing and stops, so the width of each opening comes off the run. Measure the opening, not the door: a wide archway takes far more off the run than a standard 900 mm doorway. Count every opening the skirting has to break around, and use the count and the width together.

How much waste should I allow for skirting?

About 10% is a sensible allowance. Every corner takes a cut — an internal corner is a scribe and an external corner is a mitre — and each opening needs a return, so a room with several doors, a chimney breast and a bay will use more of each length than a plain rectangle. If you are matching an existing profile that may not be available again, allow more and keep the offcuts.

Can I fix skirting with adhesive only?

Adhesive alone is not enough on its own for a long run. Grab adhesive holds the board to the wall, but a run of skirting wants mechanical fixings as well — plugs and screws, or lost-head nails into a stud — so that it stays flat and takes the odd knock without springing off. The adhesive does the holding; the fixings stop the board moving.