What you'll need
- Tape measure (at least 8 m)
- Pen and paper
- Calculator (phone is fine)
- A helper for long rooms
How to measure a room for carpet
1. Sketch the room
Draw a quick plan from above. Include doorways, chimney breasts, alcoves and built-in wardrobes. You don't need to be neat — just clear.
2. Measure the longest length
Measure the longest wall in metres. Always go into any doorways and add 10 cm to the total length for trimming. So a 4.1 m room becomes 4.2 m on your plan.
3. Measure the widest width
Measure the widest point of the room — chimney to wall, or alcove to alcove — and add 10 cm to the total width for trimming. Always measure to the widest point, not the average.
4. Round up to roll width
Carpet comes in 4 m and 5 m wide rolls (some budget ranges in 3 m). Round your width up to the next roll size so you avoid unnecessary joins. A 3.8 m wide room needs a 4 m roll; a 4.2 m room needs a 5 m roll.
5. Mind the pile direction
Carpet has a pile direction (the way the fibres lean) and looks lighter or darker depending which way you view it. The pile should run the same way through every adjoining room and down the stairs — usually towards the main light source or down the staircase. This can affect which way the roll is cut, so always note it on your plan.
6. Bay windows, recesses & doorways
Always measure to the furthest point of any bay window, alcove or chimney recess, and run the tape through every doorway up to where the next floor finish starts (usually the centre of the door when closed). Missing a 30 cm bay can leave you 30 cm short on the whole room.
How to measure stairs for carpet
Stairs are the part most people get wrong. Use these simple rules and you'll be safe.
Straight stairs
Allow 50 cm per stair (tread + riser). So 13 straight stairs = 13 × 0.5 m = 6.5 m of carpet, by the width of your staircase (usually 90 cm to 1 m).
Winders, kites and bullnoses
Each winder, kite or bullnose is cut and fitted as its own piece. Measure the longest part and the widest part of the step and add 10 cm to each for trimming. That gives you the size of the offcut needed for that step.
Landings & half-landings
Measure landings like a small room (length × width with 10 cm added to each total). If the landing carpet runs in the same direction as the stairs you can sometimes save on joins.
Common measuring mistakes to avoid
- Measuring to the skirting only — always measure into doorways and recesses.
- Forgetting the 10 cm trimming allowance on the total length and width.
- Rounding down — always round up to the next roll width.
- Ignoring pattern repeat on patterned carpets — patterns need extra.
- Guessing the stair count instead of counting from the bottom riser to the top.
- Forgetting pile direction — adjoining rooms with the pile running opposite ways look like two different colours.
- Measuring an empty room only — wardrobes, beds and radiators don't change the measurement; always go wall to wall.
Prefer to leave it to me?
I offer a free, no-obligation measure across Darlington, Newton Aycliffe, Bishop Auckland and the wider North East. I'll quote the exact metres you need so you don't over- or under-order.