The pattern on the wallpaper border and how many times it repeats in a given distance plays a part in how well it looks in the room. When you add a wallpaper border to any room, you must calculate this measurement between the repeated [pattern](http://wwwstevesblindsandwallpapercom/sb_wpMeasuringInstallationaspx), so you can expertly match it when you hang it.
You also need to know this to ensure you pick up enough of the border material to complete the room.
Things You Will Need
- Tape measure
- Calculator or notepad
- Chalk line
- Measure the room's length and widths and write these down on a notepad.
- Add these measurements together to get a total and then multiply the total by two. For instance, if the room is 12 feet long and 16 feet wide, the combined total of these two walls is 28 feet. If you plan to add a wallpaper border to the entire room, the total length needed, not counting repeated patterns would be 56 feet.
- Measure the distance between the repeated pattern and add that distance to each wall measurement. For example, if the repeated pattern occurs every 12 inches, add 48 inches or 4 feet to the room's total measurement to ensure you have enough wallpaper border to match the pattern.
- Add an extra 10 percent to the calculation to account for errors. For example, the room measurement of 56 plus 4 feet equals 60 feet. Add 6 feet for the 10 percent, and purchase enough wallpaper border to cover 66 feet. That should leave you enough material to match the pattern and with a bit left over for any cutting mistakes, needed repairs or to use for another home decor or craft project.
- Calculate the number of yards that are needed, as wallpaper border is sold by the yard. Divide 66 by 3 to arrive at 22 yards. Divide the number of yards per roll or spool -- 5 yards for example -- into 22 to arrive at a total of 4.4 rolls required. Round up to the nearest whole number. In this scenario, you'd need five rolls of wallpaper border to outfit the sample room.