How to Measure a Room for Carpet
Seven quick steps to get the right size carpet roll end first time. Measure your room from the widest point, then your stairs and landing. Roll ends are collection only and we don't fit, so accurate measurements matter.
1. Measure the widest points of your room
Use a tape measure and record the widest distance in each direction - including bay windows, alcoves and doorways. Carpet is sold from the widest measurement, never the average.
2. Add for doorways and thresholds
Add 10cm (4") to every measurement that meets a doorway or threshold so you have enough to tuck in cleanly under the door bar.
3. Note down your measurements
Note down the measurements of each room
4. Count your stairs
Count the total number of steps, including any winders.
5. Measure the stair width
Measure the width of one stair from side to side.
6. Measure one step
Measure from the back of the tread (where your foot goes) down the front of the riser (the vertical part) to the bottom, then multiply by your step count from step 4.
7. Measure the landing
Measure the length and width of the landing, adding on the height of the top step (the landing carpet wraps over the top step) and adding extra for doorways and thresholds as in step 2.
Top tips
- Always round measurements up to the nearest 10cm.
- Measure twice - it's the cheapest mistake to avoid.
- Roll ends are fixed length - pick the one that beats your longest wall.
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