Choosing the right wall covering for your home is not always an easy decision. You can select from among numerous paint colours, textures, faux finishes and wallpaper. If you decided that you want wallpaper, you need to know how much to buy. Calculating the amount of paper needed involves mathematical formulas. There is no need to fret over the thought of maths. The calculation is not difficult. Your answer takes into account the height and width of your walls, and the number of doors, windows and cabinets.

- Skill level:
- Easy

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### Things you need

- Tape measure
- Calculator

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## Instructions

- 1
Measure with a tape measure the square metres of each separate wall. Measure the width and the height of one wall and multiply one by the other. The answer is the square metres of that wall. Complete this step for each remaining wall and then calculate the total of all four numbers. The final amount that you calculate will be the total square metres of the room's walls.

- 2
Multiply separately the height and width of each door and window. Add the results to find the exact square metres that you will deduct from the total square metres of the walls. An easier method that many professional wallpaper installers use is to deduct approximately 1.4 square metres (15 square feet) for each door and window in the room, unless you have a very large opening or window.

- 3
Divide the final total square metres by 2.8 unless you are using European wallpaper, in which case you will divide by 2.3. This will tell you how many single rolls you need to wallpaper your room. Divide that number by 2 to get the amount of double rolls that you will need. Wallpaper usually isn't sold in single rolls anymore.

#### Tips and warnings

- Save a wrapper off a bolt of wallpaper. The wrapper will have a lot number on it. This number will allow you to get more paper from the same batch in case you run out.
- Most shops will allow you to return unopened packages of wallpaper if you buy too much.