A standard width of wallpaper is usually 0.53cm and 10m in length. Measure the total perimeter of the room including all doors and windows, and divide by 0.53. This will give you the total number of widths needed.
Multiply the height of the room (in meters) by the number of widths needed to get the total length of wallpaper required. Divide this by the roll length (usually 10m). This equals the total number of rolls required.
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