Wallpaper Roll Calculator
Calculates wallpaper roll requirements based on room perimeter, wall height, pattern repeat drop (0", 6", 12", 24"), and standard US double roll bolt yields (56 sq ft).
Formula
Usable Sq Ft per Roll = ~28 sq ft (Double Roll); Rolls = Ceil(Net Wall Area × (1 + Pattern Waste) ÷ Usable Sq Ft)
1. Gross Area = 2 × (Length + Width) × Height 2. Deductions = (Doors × 21) + (Windows × 15) 3. Net Area = Gross Area - Deductions 4. Pattern Waste Factor: Random=10%, Small=15%, Medium=20%, Large=25% 5. Adjusted Area = Net Area × (1 + Pattern Waste) 6. Rolls = Ceil(Adjusted Area ÷ 28 sq ft per double roll)
Inputs
- Room / Wall Length
- Room Width (or 0 for single accent wall)
- Wall Height
- Pattern Repeat Match
- Roll Packaging Standard
- Doors
- Windows
Worked example
Hanging a floral pattern wallpaper with an 18" drop repeat on a 14 ft wide by 9 ft high accent wall.
Outcome: Wall area is 126 sq ft. With 20% pattern repeat matching waste, effective area needed is 151.2 sq ft. At 28 usable sq ft per double roll bolt, 151.2 ÷ 28 = 5.4 bolts, rounding up to 6 double roll bolts.
Why are wallpaper rolls priced in single rolls but sold in double rolls?
In the United States, wallpaper is traditionally priced per single roll to allow price comparisons, but packaged and shipped as double roll bolts (continuous 11-yard lengths) to minimize seams and cut scrap.