Calculating How Much Wallpaper to Use

If you’ve decided on wallpaper for your home improvement project, you want to make sure to buy the right amount for your needs. These formulas help you determine how much wall paper to purchase:

Wall Area:

[Total Length of All Walls] x [Wall Height] = Wall Area

Unpapered Areas:

[Window Height] x [Window Width] x [Number of Windows] = Window Area

[Door Height] x [Door Width] x [Number of Doors] = Door Area

Wallpapering Area:

[Wall Area] – [Unpapered Areas] = Wallpapering Area

Wallpaper to Order:

[Wallpapering Area] ÷ [Usable Yield] = Number of Single Rolls Needed

Usable Yield Charts:

Pattern Repeat (Drop)	Usable Yield (American Rolls)	Usable Yield (European Rolls)
0 to 6 in.	32 sq. ft.	25 sq. ft.
7 to 12 in.	30 sq. ft.	22 sq. ft.
13 to 18 in.	27 sq. ft.	20 sq. ft.
19 to 23 in.	25 sq. ft.	18 sq. ft.

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