Wallpaper Rolls: Counting Rolls Without Running Short
Pattern matching eats paper, so a bare area division usually undercounts. This post shows the waste allowance and why rounding up matters.
What is the Wallpaper Rolls Calculator?
Enter the total wall area and the coverage of one roll, and the tool divides one by the other, adds a 10 percent waste allowance for pattern matching and offcuts, and rounds up to whole rolls. The waste figure is shown separately so you can see exactly what it adds.
How to use it
- Measure the total wall area in square metres.
- Enter the coverage printed on one roll.
- Click Calculate Rolls.
Worked example
40 sq m at 5 sq m per roll needs 8 rolls exactly, or 8.8 with waste, rounded up to 9 rolls.
Why add 10 percent waste?
Pattern repeats, door and window cuts, and starting a new strip all create offcuts that a plain division misses.
Frequently asked questions
Do I subtract doors and windows?
You can, but many decorators keep them in the area as a safety margin instead of cutting it fine.
What if the pattern repeat is large?
Use a bigger allowance, since large repeats waste more paper at each strip join.