Measuring for internal wallcoverings
It is important to understand a couple of concepts that are integral to wallpaper. The first thing is that wallpaper comes in several different sizes. Metric Rolls are about 21 inches wide. This makes a big difference in the amount of square footage you’ll get out of one roll or the other. The commonest UK wallpaper dimensions are 52cm width x 10m length or 20.5” x 11 yards which gives you about 35 square feet. However, there are an increasing number of papers that are 68.5cm wide, and some at 45cm width. And in recent years a number of ultra-wide width or panel designs have become available.
The most important step in estimating wallcovering is accurate measurements. Use steel tape measure, never a cloth tape measure. Take measurements in feet rounding off to the next highest half foot or foot. Draw a room diagram showing doors, windows and ceiling height. If a wall is unusually broken up with a fireplace, built-in bookcases, etc., a diagram with detailed measurements will be beneficial in figuring square footage of wallcovering needed. Measure wall height from floor to ceiling. Exclude baseboards and mouldings. Measure length of each wall including doors and windows. Find the total square feet of the wall(s) by multiplying ceiling height by total wall length. Subtract areas that will not be covered. (Standard doors are about 3 x 7 feet or 21 square feet; standard windows about 3 x 4 or 12 square feet.) These calculations give the total number of square feet to be covered. Using this number of rolls or linear yards of wallcovering can be determined.
In the above figure, each wall is 12” long with an 8” ceiling. Multiply 12 x 8 = 96 square feet for each wall, then multiply 96 x 4 (since there are four walls with 96 square feet each)= 384 total square feet for the room.
These figures work well for normal-sized walls. For unusually short (under 3 feet) or high (over 9 feet) they do not apply.
Basic Standard-sized Wallpaper Roll Calculator Chart to find out the quantity.
Stairways or Cathedral Walls
When estimating a wall that has a diagonal, remember there will be extra waste to allow for the slope of the steps or the ceiling pitch. There are two different types of stairways to figure: one with a horizontal ceiling line, and the second with a diagonal ceiling line that parallels the fall of the steps.
In both cases, the first step is to divide the wall in either squares or rectangles to determine the square footage. In the figure given above, the upstairs ceiling height is 8″ and the downstairs ceiling height is 8″. These figures are the length of the wall. Next, measure wall width horizontally from the top of the stairs to an imaginary vertical line originating at the bottom of the stairs, which in the example is 15″
Taking the top rectangle, figure 8″ x 15″ = 120 sq. ft. Next, figure the bottom rectangle, 8″ x 15″ = 120 sq. ft., but since a portion of this wall area is under the stairs, multiply the bottom rectangle square footage by 65%, an industry standard.
Add the two figures together to arrive at the square feet that needs to by hung with wallcovering.
The equation would look as follows:
8″ x 15″ = 120 sq. ft. (top rectangle)
8″ x 15″ = 120 sq. ft. x 65% = 78 sq. ft. (bottom rectangle)
120 sq. ft. + 78 sq. ft. = 198 sq. ft.
Once you have the square footage figured, estimate the amount of wallcovering just as you would for an ordinary room, finding the usable square feet for the particular pattern from the Usable Yield Chart and then dividing the total square feet by that figure.
For example, if using a wallcovering with repeat of 14″ each single roll would contain 20 square feet of usable wallcovering. The equation would look as follows: 198 sq. ft. / 20 sq. ft. = 9.9 rounded to 10 rolls.
If the stairway has a sloping ceiling, do as the first example in finding the width and length of the imaginary rectangle or square. The next step is to take both of these rectangle/square figures multiplied by 65% to find the square feet of wall area.
The equation would look as follows:
8″ x 15″ = 120 sq. ft. (top rectangle)
8″ x 15″ = 120 sq. ft. (bottom rectangle)
120 sq. ft. + 120 sq. ft. = 240 sq. ft.
240 sq. ft. x 65% = 156 sq. ft. of wall area to be covered
Using the same pattern with a repeat of 14″ each single roll would contain 20 square feet of usable wallcovering and the equation would look as follows:
156 sq. ft. / 20 sq. ft. = 7.8 single roll rounded to 8 rolls.
A cathedral ceiling would be estimated the same way, squaring the top rectangle, multiplying the square feet by 65%, and then adding that figure to the square feet of the bottom rectangle.
Top tips:
Important – Remember only to count full drops here – e.g. 2.78 should be rounded down to two drops. If in doubt, always over order. If you order too little and have to order more, you could receive a roll from another batch, where colour or pattern differs slightly.
NOTE: The above dimensions are mostly shown in imperial measurements if you prefer to work in metric there are many online calculators that can assist you accurately convert imperial measurements to metric.
