How To Measure For A Wall Mural Wallpaper

By Author: Dipan Patel
Total Articles: 2
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A wall mural can be the moment a room finally feels finished—like the space has a point of view. But before you fall in love with a design, there’s one unglamorous step that makes or breaks the whole project: measuring.

Measuring for wallpaper murals isn’t hard, but it is different from measuring for regular repeat wallpaper. Murals are one big image (usually delivered in numbered panels), so the sizing has to be right—especially when you’re working around panels, doors, and windows. The goal is simple: order enough mural to cover the wall comfortably, then trim cleanly on site for a seamless, professional finish. The same approach applies whether you’re installing a traditional mural or a peel and stick wallpaper mural.

Before you start: what you’ll need

You don’t need fancy tools—just a few basics:
• A tape measure (a long one is better)
• A notepad or notes app
• A pencil (if you’re sketching)
• A step stool for tall walls
• Painter’s tape (optional, but helpful for marking points)

Quick tip: Pick one unit—inches or cm—and stick ...
... to it the whole time to avoid conversion mistakes.

Step 1: Decide exactly what you’re covering

Start by looking at the wall and deciding what “coverage” means for your space:

• Full wall: corner to corner, ceiling to baseboard (most common for wallpaper murals)
• Partial wall: above wainscoting, below a picture rail, or inside a framed section
• Feature area: one section of a larger wall, like behind a bed or sofa
If you have wall panels (like wainscoting or decorative trim), decide whether your mural will:
• Go over the panels (common and often easiest), or
• Sit inside specific panel frames (more detailed and usually a custom look)

Once you know the area, measuring becomes straightforward.

Step 2: Measure the wall width (in three spots)
Most walls aren’t perfectly straight, even in newer homes. That’s why you should measure the width in three places:

1. Near the ceiling
2. At the middle of the wall
3. Near the baseboard

Write down all three numbers, then use the largest measurement. That gives you the safest width to order.

Add a little breathing room

For murals, it’s smart to add a margin so you can trim neatly—especially if corners aren’t perfectly square.

A good guideline is:

• Add 2–4 inches (5–10 cm) to the total width
This is particularly helpful with a peel and stick wallpaper mural because you want enough material to reposition and still trim clean edges.

Step 3: Measure the wall height (also in three spots)
Now do the same for height, measuring:

1. Left side
2. Center
3. Right side
Use the largest number.

Then add:

2–4 inches (5–10 cm) extra height

What about baseboards and crown molding?

In most installs, people keep baseboards and trim the mural just above them. Crown molding is personal preference—some cover up to it, some stop below. Either way, decide first, then measure for that decision.

Measuring walls with panels (wainscoting, fluted panels, framed trim)
Panels can make you second-guess yourself, but measuring is easier than it looks.

Option A: The mural goes over the panels (most common)

Treat the wall like a full flat surface:
1. Measure the full wall width and height as described above
2. Add your margin
3. Make a note of the panel texture (deep grooves may need extra prep)

Heads-up: If the paneling has deep grooves or heavy texture, adhesive may not sit smoothly. For the best finish, many people prep the wall with a liner or smoothing method so the mural—especially peel and stick—lays flat.

Option B: The mural fits inside panel sections (custom approach)
If you want the mural inside framed panel boxes, measure each section separately:

• Measure the inside width and height of each panel opening
• Note the spacing between them
• Sketch the layout so you understand where the mural image will land

This looks incredible when done well, but it needs more planning because the mural image may need custom cropping.

Measuring around doors (don’t subtract—plan the placement)

This is where people often overthink it: you usually do not subtract the door area. With wallpaper murals, you measure the full wall and cut around the door during installation so the design stays aligned.

Here’s what you should measure:
1. Full wall width + height (largest measurements, plus margin)
2. Door width + door height
3. Door placement:

Distance from the left corner to the door frame
Distance from the floor to the top of the door trim

This placement info helps you avoid awkward cuts—like a mural seam landing directly on the edge of the door trim.

Pro tip: If you can, plan your panel layout so seams don’t sit right on door frames. It’s harder to trim cleanly and more likely to lift over time.

Measuring around windows (same rule: don’t subtract)
Windows are measured the same way as doors: measure the full wall, then capture window size and position so you can plan around it.

Measure and note:

• Window width and height (the opening)
• Distance from the floor to the window sill
• Distance from the ceiling to the top of the window trim
• Distance from the left corner to the window trim

If you have multiple windows, measure each one—don’t assume they’re identical.

Design note: If your mural has a clear focal point (like a central motif, skyline, or horizon line), try to position it so it doesn’t get sliced through the middle by a window opening.

A quick word on mural panels (and why your measurements matter)

Most wallpaper murals arrive in panels. Your measurements help you:
• Avoid ending up with a tiny, awkward strip at the edge
• Keep the artwork balanced on the wall
• Place seams away from tricky areas like trim, corners, and door frames

If the mural is a statement piece, it’s worth spending five extra minutes planning where the “center” of the design should land—especially in rooms where furniture naturally frames the wall (behind a bed, sofa, or dining table).

Common measuring mistakes (easy to avoid)
• Measuring only once instead of three times
• Forgetting to add margin for trimming
• Subtracting doors and windows (usually unnecessary)
• Ignoring sloped ceilings, soffits, or bulkheads
• Assuming corners are perfectly square

A careful measure now saves a lot of frustration later.

Pro tips for installing a peel and stick wallpaper mural

Peel-and-stick murals are popular for a reason: they’re approachable, renter-friendly, and easier to reposition than paste murals. To get a clean finish:

• Start with a clean, smooth, properly primed wall
• Use a level to mark a straight vertical starting line
• Lay panels out on the floor first to confirm the order
• Work slowly and smooth as you go to prevent bubbles

Quick measuring checklist (copy/paste)
• Measure wall width at top/middle/bottom → use the largest
• Measure wall height at left/center/right → use the largest
• Add 2–4 inches (5–10 cm) to both width and height
• Measure doors/windows but don’t subtract
• Record door/window placement from corners and floor
• Note wall panels and texture

Measuring for wallpaper murals doesn’t need to feel technical. It’s really just about giving yourself enough material to work with, then trimming for a perfect fit. Take your time, measure in a few spots, and write everything down clearly.

And if you’re ordering a peel and stick wallpaper mural, those extra inches of margin are your best friend—they give you room to align panels neatly and finish with crisp, professional edges.
If you’d like, share your wall width and height plus the position of any doors or windows, and I can help you double-check the numbers and plan the cleanest panel layout.