Home improvement

Baseboard and skirting board calculator

Perimeter minus doorways, plus waste for mitred corners.

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Baseboard and skirting board calculator
The four sides added up. In an L-shaped room, go all the way round.
Count them only if they are not being painted. Left blank we use 0.
The face you see, without the joint.
Advanced options
%
Extra material for cuts, breakage and adjustments. Left blank we use 10.

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Your result will appear here

There is no figure yet: nothing is calculated until you ask for it.

  1. Enter your measurements.
  2. Check the units and the assumptions.
  3. Press Calculate, or load the example.

Rather see a worked case? Press “Load example” and change any value afterwards.

Next step

Paint calculator

Baseboard and wall get painted together, from the same perimeter.

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Where each number comes from Conversion constants are exact; densities and coverage rates come from cited sources; everything else is an assumption you can change. Methodology · Sources and updates

How to use it

  1. Add up the room perimeter.
  2. Say how many door openings there are and how wide.
  3. Enter the length of the lengths sold at your store.
  4. The result gives whole lengths and the offcut.

How it is calculated

Perimeter minus doorways, plus waste, divided by the length of a piece:

length = perimeter - (doors x opening width) length with waste = length x (1 + waste) pieces = ceiling(length with waste / piece length)

The 10 % waste exists because of mitres. Every corner eats a few centimetres, and one badly measured cut costs half a length, because the offcut almost never matches what the next wall needs.

The result rounds to whole lengths because baseboard is sold in sticks, not by the metre. The leftover is shown so you know what you are left with.

Worked example

A room with a 46 ft perimeter, one 32 in doorway, 8 ft lengths, 10 % waste:

  • Perimeter minus doorway: 46 - 2.6 = 43.4 ft
  • With waste: 43.4 x 1.10 = 47.7 ft
  • Pieces: 47.7 / 8 = 5.96 → 6 lengths (48 ft)
  • Left over: 0.3 ft

That 5.96 is exactly why you round up: six lengths leaves you finishing with inches to spare, five leaves a wall bare.

Good to know

  • Baseboard and skirting board are the same thing. The name changes by country; the maths does not.
  • External corners waste more. An external mitre wastes more than an internal one. With many corners, raise waste to 15 %.
  • Buy one spare length. If the profile is discontinued, replacing a damaged run is impossible without it.
  • Measure with the floor down. Baseboard goes on after the flooring and sits on it.

Frequently asked questions

How much baseboard do I need for a room?

For a room with a 46 ft perimeter and one 32 in doorway, 47.7 ft including 10 % waste. With 8 ft lengths, that is 6 pieces.

Are doorways subtracted?

Yes: no baseboard runs across a door opening. Enter how many openings there are and their width and they come off the perimeter.

How much waste should I allow?

10 % for a normal room. 15 % if there are many external corners or alcoves, because every mitre wastes material.

What lengths does skirting board come in?

8 ft is common in the US; 2.4 m in Europe, with 2.2 and 2.9 m also sold. Enter the real length you are buying: it changes the piece count.

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