Wallpaper calculator
How many rolls to paper a wall or a whole room, counted the way decorators count: in drops.
9 rolls.
- Drops across the wall
- 27
- Each drop, with trim and repeat
- 2.70 m
- Whole drops per roll
- 3
How it works it out
Wallpaper is hung in drops: full-height strips, one roll-width wide. The width of wall divided by the roll width, rounded up, is how many drops you need. Each drop is the wall height plus 10 cm to trim top and bottom, lengthened to a whole number of pattern repeats so the pattern lines up from one drop to the next.
A roll gives only whole drops, since an offcut too short for a full drop is waste. The drops needed divided by the drops per roll, rounded up, is the rolls to buy. Doors and windows are not taken off: the paper round them is still cut from whole drops.
Questions
How many rolls of wallpaper for a feature wall?
A 3.5 m wide, 2.6 m high wall takes 7 drops of standard 0.53 m paper. With no pattern repeat, a 10.05 m roll gives 3 drops, so 3 rolls.
What is a pattern repeat?
The height after which the pattern starts again, printed on the label in cm. Each drop has to start at the same point in the pattern, so a large repeat can mean fewer drops from each roll, and more rolls.
What size is a roll of wallpaper?
Most are 0.53 m wide and 10.05 m long. Wide non-woven rolls are 1.06 m wide and 10.05 m long: half the drops, and fewer seams.
Should I buy an extra roll?
One more than the count is sensible for anything with a pattern, a first attempt, or an awkward room. Check every roll carries the same batch number: shades vary between print runs.