How we calculate rolls
We adjust the drop length to the next pattern-repeat multiple, work out how many complete drops fit in each roll and how many are needed around the room with margin.
adjusted drop β drops per roll β total drops β rolls
What pattern repeat means
It is the distance before the design repeats. Matching the pattern can require a longer cut than the actual wall height.
Why the estimate is conservative
Doors and windows reduce net area but often do not remove an entire wallpaper drop. Extra material from the same batch is safer.