A common method of estimating wallpaper for a room is to calculate square footage. However, Hogan warns that this can leave you short.

It is better to calculate by hand and take into account areas occupied by doors and windows. That way, you will have enough left over to trim and cover any mistakes.

Find the Surface Area of Your Walls

Most wallpaper measuring guides advise calculating square footage for your walls, but Hogan says that this method can leave you short of the amount needed. He suggests determining the number of usable, floor-to-ceiling strips that can fit on each roll instead. This can eliminate the need to subtract areas taken up by doors, windows or other interruptions that will make it difficult to line up the pattern.

To find the width of your wall, measure across it with a tape measure and add all the measurements together (this is known as the total combined width). Then divide the width of your wallpaper by its pattern repeat allowance (see product specifications for more information) to work out how many full drops you will get from a single roll of wallpaper. I recommend this website for more wallpaper singapore.

Add the height of your room to this number and multiply it by the wallpaper height allowance to find the total height measurement in metres – remember to always round up to the nearest whole number. Now add this to the total width of your wall in metres and divide it by the length of a wallpaper roll in metres to work out how many rolls you will need.

Measure the Pattern of the Wallpaper You Want

Many patterned wallpapers have a vertical pattern repeat, and you’ll need to know the length of the repeat. This can usually be found in the product specifications or on the back of your wallpaper sample book.

To find out how many strips you’ll need for a given height, multiply the width and length of each wall together. If you have openings such as doors and windows, subtract them from the total.

Then, divide the number of strips required by the amount of paper in a single roll. This will tell you how many full strips you can expect to get from a double or metric roll (9 yards, or 27 feet long). Always round up to the next number, to ensure that you have enough to cover your walls and to allow for any hiccups during installation. This hand calculation method is generally less time consuming than using online calculators. It also gives you the added confidence of knowing that you have a good estimate for your project.

Multiply the Surface Area of Your Walls by the Amount of Wallpaper in a Roll

A single wallpaper roll usually covers about 27 square feet of wall space. This is a little more than you need for the average sized room, but it gives you some extra room to account for pattern matching and trimming.

To find out how much space you need for a single roll, add the lengths of all your walls together to get your room’s perimeter. You can then multiply that number by the height of your walls to find out how many square feet of space you have. Be sure to subtract the area of any normal sized doors or windows you have in the room.

Now you’ll need to figure out how many full strips of wallpaper can fit on a single roll of your chosen type and style. Most manufacturers list this information on their website or in their catalog. This will help you avoid overestimating how much wallpaper you need and wasting money.

Divide the Number of Rolls You Need by the Amount of Wallpaper in a Roll

Most wallpaper is sold by the double roll (28 yards or 27 feet of usable length). To figure out how many rolls you need, divide the total room square footage by this number. This allows you to get an accurate estimate of the amount of wallpaper you need without worrying about dye lots, which can cause variations in color from roll to roll.

Remember to include the area of doors, windows and other special wall areas when you’re measuring the room. You should also add the height of your ceilings to the height of your walls, adding in any pattern repeats if necessary. This helps you find a more realistic estimate of how much wallpaper you need without excluding spaces that may require extra material because of their dimensions or because of a complicated pattern repeat. This can help prevent you from ordering too little and having to spend more money on wallpaper in the future.