If you are ready to determine how much wallpaper you’ll need for your room and how much it’s going to cost then this post is for you!
While this task may seem overwhelming at first, don’t worry – its just some simple measurements and basic math!
We’ll walk you through it step by step.
Let’s imagine we are wallpapering all four walls of a 10’ x 12’ square bedroom with a ceiling height of 10’ using the horribly busy butterfly wallpaper pictured at right.
You will need the following room measurements:
- The length of every wall you’ll be papering (measured in feet)
- The height of the ceiling from where the wall meets the baseboard to where the wall meets the ceiling, or the crown molding. (measured in feet)
You will need the following measurements from the wallpaper itself:
- The roll width (measured horizontally in inches)
- The repeat. Your wallpaper’s repeat is the vertical measurement of the pattern on the wallpaper from any starting point up or down to where the pattern begins to repeat itself. (measured vertically in inches)
The vertical repeat of the wallpaper pattern will be listed in your HMD design package, on the manufacturer or seller’s product information pages and/or on packaging of the roll of the wallpaper.
Calculating The Number of Rolls Needed
Now that you’ve collected all of the important measurements, here’s how we calculate quantity and ultimately the price of your materials.
- Add together the total total length in feet for all walls: Our example room the numbers would be 10′ + 12′ + 10′ + 12′ = 44 feet.
- The tallest ceiling height: Our example room was 10′ from the wall’s lowest point at the floor to its tallest point on the ceiling. You are going to need to convert this into inches for use in step three by multiplying the height in feet by 12. Our example measurement is 10′ x 12″ = 120 inches.
- The vertical repeat of the wallpaper pattern: Divide the height of the wall (inches) by the vertical pattern repeat.
- Using our example room, we’ve converted the height in inches to 120”
- Let’s say our wallpaper’s vertical pattern repeat is 18” therefore we divide 120” by 18” = 6.66. Always round up! Our number of repeats then will be 7 (the pattern repeats itself seven times from floor to ceiling).
- Multiply the number of repeats (7) by the vertical pattern repeat measurement (18”) and we get 126”. This is the adjusted height of the wall that we will use to calculate the number of rolls needed to be purchased for this specific wall paper. This ensures that we will have enough extra on each strip of cut wallpaper for wiggle room when making sure the pattern lines up from width to width. So, instead of using the true ceiling height of 10’, you will use 10.5’ (126” from the example above converted into feet = 10.5’) Get it? now we have 6″ extra to shift the strip of wallpaper up or down to match up the pattern.
Calculating the Total Yardage and Number of Rolls Needed
With the above three measurement calculations, now you can use a handy online tool to calculate your final yardage requirements.
Using our above example and assuming our sample of horribly busy butterfly wallpaper roll width is 36”, the calculator shows that we need 52 linear yards to cover the entire room.
Finally Determine Cost Based Upon Using Single Rolls and Double Rolls
Most rolls are priced and measured as a single roll, but are sold as a double roll.
If our example wallpaper roll is 11 yards long we would need 5 single rolls for the entire room (11 yards x 5 rolls = 55 linear yards which meets the requirement of 52 linear yards indicated by the calculator), but since our wallpaper is only sold in double roll quantities we’d need to determine our price according to purchasing the 6 single rolls quantity.