Measure the full width
Measure from the far left edge to the far right edge at the top, middle and bottom of the wall. Keep the tape straight and record the largest width.
How to Measure a Wall for Wallpaper
How to Measure a Wall for Wallpaper
Accurate measurements are the foundation of a made-to-measure mural. Follow this guide before ordering so your design arrives at the correct size and has enough room for a clean final trim.
Use centimetres or inchesChoose one unit and use it consistently. Our calculator accepts both cm and inches.
Measure more than onceWalls, ceilings and floors are not always perfectly straight.
Use the largest valueNever average measurements or subtract doors and windows.
The four essential steps
Measure the full height
Measure from ceiling to floor on the left, centre and right. Use the largest height, even if the difference is small.
Include doors and windows
Measure the complete outer rectangle of the wall. Do not subtract windows, doors, sockets or other openings; these areas are trimmed during installation.
Add a safety margin
Add 5 cm (2 in) to the total width and 5 cm (2 in) to the total height unless the product instructions state otherwise. This allows for walls that are slightly uneven and gives you room for precise trimming.
Important: enter the total mural size
When ordering, provide the full finished wall width and height including the recommended margin—not the width of an individual wallpaper panel.
Walls that need extra attention
Sloped walls
- Measure the wall at its highest and widest points.
- Treat the area as one complete rectangle or square.
- Ignore the slope when ordering; trim the angled section during installation.
- Add 5 cm (2 in) to both the total width and height.
Walls with several slopes
- Measure the longest width and the greatest height.
- Order the complete surrounding rectangle.
- Trim every angled section only after the wallpaper is positioned.
- Add the same 5 cm (2 in) safety margin to width and height.
Multiple connected walls
- Add together the widths of all walls.
- Add 5 cm (2 in) of safety margin for each wall.
- Use the height of the highest point and add 5 cm (2 in).
- For one continuous mural, send us a sketch showing each wall, corner and measurement before ordering.
Staircases
- Measure the highest and lowest height points and the complete width.
- Use the maximum width and height to create a full rectangle.
- Trim the staircase slope during installation.
- Contact us if an important part of the design needs precise placement.
Common measuring mistakes
Subtracting doors or windows
Always order for the complete wall rectangle. Subtracting openings can affect the scale and alignment of the design.
Measuring only once
A small variation can leave part of the wall uncovered. Measure width and height in at least three places.
Using architectural plans instead of the finished wall
Plans may not reflect plaster, skirting boards or construction tolerances. Measure the actual finished surface.
Ordering the exact measurement with no margin
A small allowance makes final alignment and trimming much safer, especially in older properties.
Measurements ready?
Choose your wallpaper design and enter the final width and height. If your wall is unusual, send us the measurements and a photo before ordering.
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