How to calculate how much wallpaper you need?

Wallpaper installation may seem a little bit complicated but believe us it is not!  A lot of people getting scared at their very first step of the installation which is measuring walls and calculate how many rolls they will need. Let me try to help you here with some tips on this topic.

Let’s figure out: How much do you need? It may seem confusing just because not all wallpaper rolls have the same measurements. Wallpaper is usually sold in different roll sizes: single rolls, double rolls, triple rolls, quadruple rolls. So first, check the description and figure out in what size does that wallpaper comes in. Here we will provide a tab for you which may help to calculate how many rolls you may need. Our tab is created using a standard “double roll” size (1.74 ft wide by 33 ft long) which usually covers around 56 sq.ft. If the size of the roll that you are planning to buy is different, it may not help you, but I will provide a formula for calculating it by yourself without using this tab.

How to measure your walls properly? In order to calculate how many rolls of wallpaper you may have to order you will need to know your wall or walls sizes: height and width. If you have few walls with the same height, add all walls width together, so you will have 2 numbers: height and total width. Usually, unless you are already a professional and know where to start your installation in order to save some wallpaper, do not exclude doors, windows or other objects from your measurements.

Now, when you know this information, go back to your wallpaper description and find out the length of the roll (it is usually 33 ft, 24 ft or 18 ft, but may be different). Divide the length of the wallpaper (33 ft or 24 ft or other if applies) by your wall height in feet (for this example I will use 9 ft height wall). The number that you have received (probably not the whole number but will look like 4.125 or 3.6666 or other) reflects how many lines of the wallpaper you will receive out of 1 roll of that wallpaper. So just round up that number to the whole lower number (for example 3.6666 will be 3 full lines, 4.125 will be 4 full lines) Now you know how many lines you may receive out of the roll. You can now multiply this number by the width of the wallpaper (1.74 ft, 2.24 ft, 3 ft or other wallpaper width) that you are planning to buy (width in feet). For my example I will use 2.24 ft with of the wallpaper. So if the width of the wallpaper is 2.24 ft and my wall height is 9 ft ( 3 lines that I will get out of the roll if the wall height is 9 ft) I multiply 2.24 ft x 3 lines = 6.72 ft is the width of the wall that I will be able to cover with 1 roll of that particular wallpaper. This gives me an idea of the coverage. Knowing our wall width, we can now easily divide that wall width by the number that we have received from our previous calculation (width covered by 1 roll of that wallpaper), and we will receive the number of wallpaper rolls that we need to use to cover the entire wall. 

For example, we will use the wall which is 13 ft wide and 9 ft height and the wallpaper roll measurements will be 2.24 ft wide by 33 ft long:

1. Divide length of the wallpaper by the height of the wall: 33 ft by 9 ft = 3.666 – which means 3 full lines out of each roll I can use.
2. Multiply 3 lines by 2.24 ft width of the wallpaper = 6.72 ft wide area that 1 roll will cover.
3. Dividing 13 ft by 6.72 ft and 1.93 is the number that I’m receiving. I’m rounding it up now to the higher number, which is 2, that means I need 2 rolls of that wallpaper if I’m doing 9 ft height by 13 ft wide wall with the wallpaper that measures 2.24 ft wide x 33 ft long.

It is important to figure out how much wallpaper you need right away, and sometimes even better to buy extra, as that particular wallpaper may not be available in the future no more and it may ruine your whole project in case you are short. Some wallpaper, even when it is the same pattern and color, may be from the different batches (different dye lot). This means that those rolls where not produced at the same time, as a result there is a possibility of the color difference between them. Request wallpaper to be shipped from the same lot if possible, or use wallpaper from the same lot on one wall and the other lot on the other wall if possible, in this case you will not see the difference in color. 

I hope it is not too confusing and I was able to explain you how to use this formula for your calculations. But if you still in doubt do not hesitate to call or email us and we will gladly help you with your questions and calculations.