# How to calculate the number of wallpapers on the room

The first step is to determine the perimeter of the room. Remember math in elementary school? The formula for calculating the perimeter is simple: (width + length) x 2. This is if your opposite walls are the same, that is, the room is strictly rectangular. If the room is complicated, the walls are broken and of different lengths, then the formula of the perimeter will look different: A1 + A2 + A3 + A4. That is, each wall will have to be measured separately, and then everything is folded in order to get the perimeter. Similarly, the perimeter is calculated if there are niches or protrusions in the room.

For example, we have a standard rectangular room with walls of 3 and 5 meters. The perimeter is 16 meters. Now, we calculate how many strips of wallpaper we need. The width of the roll is mandatory on the packaging! It can be 50 or 100 centimeters. Metro wallpapers today, by the way, are enjoying increasing popularity – yes, they are a bit harder to glue, but the process itself is faster.

So, if we have a roll width of 50 centimeters, we need 16: 0.5 = 32 stripes of wallpaper. At meter width, respectively, 16 bands.

Now, we need to find out how many bands we get from a single roll of wallpaper. To do this, we need two indicators – the length of the wallpaper itself and the height of the room. If there is no problem with the first indicator, it is also written on the package, then questions arise with the second one.

Yes, you can easily measure the height of the room with a tape measure. Suppose you got 2.5 meters. You need a stock of 10 centimeters for the lower and upper trimming of the strip. But if wallpaper with a pattern, a pattern that needs to be picked up, rapport should also be taken into account.

Reporting can be without displacement and offset. For example, in order to match the patterns of the strips, you will have to stick each of the next cut web by pushing up half the rapport. In this case, this value must also be added to the height of the room.

Take the most difficult option – rapport 50 centimeters, offset 25 centimeters. Remember that we have a ceiling height of 2.5 meters. 250 + 50 + 25 + 10 (for trimming) = 335 cm The height of one strip.

The standard length of the roll is 10 and 15 meters. 10 meters divided by 3.35 = 2.985, rounded to 3. That is, from one roll of 10 meters in length, we will have only 3 lanes. We also need 32 strips in width of 50 centimeters or 16 strips with a width of 1 meter. Thus, for a room with a perimeter of 16 meters, we need 32: 3 = 10.66, that is, 11 rolls. Or 16: 3 = 5.33, that is, 6 whole rolls of meter wallpaper.

If there is no rapport, wallpaper with a chaotic pattern or a pattern that you do not need to pick, then the situation is simplified and the cost of wallpaper is much less. In this case, we simply divide the length of the roll into the height of the room plus the margin for trimming.

On the question, whether it is necessary to deduct from the perimeter of the room the sizes of windows and doors, experts answer – it is not worth it! Let there be a reserve. An exception, of course, is to be done for a panoramic window with a large area. Or for a double sliding door.

In addition, take on one roll of wallpaper more than you need! Let it be in the case of a marriage or a corrupted strip. In addition, the stock will be useful if you need to pile a couple of bands in the future.