How to Measure for Wallpaper
Here’s how to measure your walls and calculate exactly what you need.
Knowing how to measure for wallpaper feels like a high-stakes maths test, but I promise it's simpler than it looks. Whether you’re in a brand-new build or a 1920s home with "character" (like mine), here is how to get an accurate count and avoid the "oopsie" moments.
How to Measure Your Walls
Step 1: The Three - Point Check
Walls are rarely perfectly square. To avoid a gap at the top or a short edge at the bottom, measure your wall height in three places: the left, the center, and the right.
- The Golden Rule: Always use the tallest height and widest width as your final numbers.
- Sloped Ceilings: If your ceiling angles down, measure to the highest point. We want the pattern to be continuous even as the wall height changes.
- Chimney Breasts: Don't forget to measure the "returns" (the side depths). Those extra inches are easy to miss!
Measuring Around Windows and Doors
Step 2: Ignore the Obstacles
When measuring your width, act as if your windows and doors aren't there. My wallpaper is printed in full-length vertical panels. To keep the pattern matching perfectly across the room, the panels need to run straight over the window or door frame.
You’ll simply smooth the paper over and trim the excess away during installation. It feels like waste, but it’s the secret to a professional, seamless finish.
How Much Wallpaper Do I Need?
Step 3: calulating how many rolls you need
Once you have your numbers, you can use the calculator below for a quick estimate. I always recommend adding 10% extra to your total. This covers the "trim factor," pattern matching, and gives you a safety net if a cut goes wrong.
The "Double-Check" Manual Method
If you’re like me and prefer to do the math yourself (or just want to triple-check the computer!), here is how to work it out manually using inches:
- Find your total width: Take your widest wall measurement in inches.
- Divide by roll width: Divide that number by 30" (my standard roll width).
- Round up: If the answer is 3.2, you need 4 panels. Always round up to the next whole number—you can't order half a panel!
- Check your height: Ensure your wall height fits within the roll length (usually 8ft, 10ft, or 12ft).
The "Batch Match" Rule: Wallpaper is printed in batches, and colors can vary slightly between them. It’s much safer (and cheaper in the long run) to order one extra roll now than to run short later and risk a slight color mismatch with a new batch.
Wallpaper Calculator
Choose your units
Got more than one wall? Measure each wall separately and add the panel counts together.
Still staring at the tape measure?
If the numbers aren't making sense, don't guess. Knowing how to measure for wallpaper is half the battle, so send me your dimensions and a quick photo, and I'll do the maths for you.
Next Steps
Now that you’ve got the numbers, it’s time for the best part, choosing the design (if you haven't already). Whether you’re looking for a bold statement or a subtle textured look, I’ve organized everything to help you find your perfect match.
check out the blog for other wallpaper tips
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