How it is calculated
- Drops per roll = roll length ÷ (wall height + pattern repeat + 5 cm trim), rounded down.
- Drops needed = wall perimeter (minus door/window widths, roughly) ÷ roll width, rounded up.
- Rolls = drops needed ÷ drops per roll, rounded up.
A common European roll is 10.05 m × 0.53 m.
Worked example
A room with 15 m perimeter, 2.6 m high, using 10.05 × 0.53 m rolls with no repeat: 3 drops per roll, 29 drops needed, so 10 rolls.
Frequently asked questions
What is pattern repeat?
The vertical distance after which the design repeats; it is printed on the roll and adds waste.
Should I buy an extra roll?
Yes, one extra from the same batch number to avoid shade differences.
Wide-width wallpaper?
Change the roll width and length to the product’s (e.g. 1.06 m).