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The estimate uses about 56 usable square feet per double roll and includes 15% for matching and cuts.Enter your measurements
Wall area × 1.15 allowance divided by 56 usable ft² per double roll.
How this estimate works
Wall area × 1.15 allowance divided by 56 usable ft² per double roll.
Measure twice and use the same unit throughout. Product coverage, material density, installation patterns, and local requirements can change the quantity you need.
Quick answer
Estimate wallpaper by multiplying room perimeter by wall height, allowing for pattern matching and cuts, then dividing by the usable coverage printed for the selected roll. Round up to complete rolls from the same production batch.
Worked example
A 14 × 12 ft room with 8 ft walls has 416 ft² of gross wall area. Adding 15% gives 478.4 ft²; at 56 usable ft² per double roll, the estimate rounds up to 9 double rolls.
Assumptions
- The room is rectangular and wall height is uniform.
- The estimate uses 56 usable ft² per double roll.
- A 15% allowance represents ordinary matching and cutting, not a large pattern repeat.
Why is usable roll coverage important?
Wallpaper labels can describe total material area, but pattern repeat and trimming reduce the wall area one roll can cover. Use the manufacturer's usable coverage or strip-count instructions whenever they are available.
Should doors and windows be subtracted?
For a quick room estimate, leaving typical openings in the gross area provides material for matching and offcuts. A room with unusually large openings can be divided into wall sections, but keep enough full-length strips for the layout.
When is a larger allowance needed?
Large repeats, half-drop matches, sloped ceilings, many corners, and damaged strips can increase waste. Confirm the pattern repeat, match type, roll dimensions, and batch number on the actual product label.
Last reviewed September 22, 2026. Source: Wallcoverings Association guide to estimating wallpaper. Product instructions take priority over a general estimate.