About This Calculator
This calculator helps you determine the number of wallpaper rolls required for your room. It accounts for room perimeter, ceiling height, pattern repeat (for matching patterns), and includes a wastage allowance.
Pattern repeats significantly affect wallpaper usage - papers with large repeats require more rolls as each strip must start at a matching point in the pattern.
How to Use
- Measure the room perimeter (add up all wall lengths)
- Measure wall height from floor to ceiling
- Check roll width and length on the wallpaper packaging
- Note the pattern repeat (0 for plain/textured papers)
- Estimate area of doors and windows to deduct
- Add wastage allowance (10-15% recommended)
Standard Roll Sizes
European Standard
10m × 530mm
~5.3m² per roll
UK Standard
10m × 520mm
~5.2m² per roll
Wide Width
10m × 700mm
~7m² per roll
Double Roll
10m+ × 1000mm
Covers more area per roll
Pattern Repeat Guide
| Pattern Type | Typical Repeat | Impact |
|---|---|---|
| Plain/Textured | 0mm (free match) | Minimal waste |
| Small Pattern | 50-150mm | Low waste |
| Medium Pattern | 200-400mm | Moderate waste |
| Large Pattern | 500mm+ | High waste, more rolls |
Important Tips
- Always buy all rolls from the same batch number for colour consistency
- Buy an extra roll for future repairs (wallpaper patterns are discontinued)
- Pattern repeat significantly increases wallpaper requirements
- Measure twice - mistakes are costly with patterned paper
- Check roll length - some are 10.05m, others may be 8m or 15m
Ready to Calculate?
Enter your room dimensions and wallpaper specifications to get accurate roll counts.
Launch CalculatorCACalifornia Building Code (Title 24)
References & Sources
Standards Cited
- American Single Roll — Standard American Single Roll Wallpaper Dimensions
Defines the standard American single roll as approximately 27 inches wide x 27 sq ft of coverage; wallpaper in North America is typically sold in double rolls - WIA/NGPP Guidelines — Wallcovering Installers Association / National Guild of Professional Paperhangers — Installation Guidelines
Industry guidance on pattern matching, wastage allowances, and strip calculation methods for North American wallpaper installation
Formulas Used
- Wall Area:
wallArea = roomPerimeter x wallHeight
Source: Standard geometry - Net Area:
netArea = wallArea - doorsWindowsArea
Source: WIA/NGPP installation guidelines - Effective Strip Height (with pattern):
stripHeight = ceil(wallHeight / patternRepeat) x patternRepeat
Source: WIA/NGPP installation guidelines — Each strip must start at a pattern repeat boundary for pattern matching - Strips per Roll:
stripsPerRoll = floor(rollLength / effectiveStripHeight)
Source: WIA/NGPP installation guidelines - Total Strips:
totalStrips = ceil(roomPerimeter / rollWidth)
Source: WIA/NGPP installation guidelines - Rolls with Wastage:
rolls = ceil(ceil(totalStrips / stripsPerRoll) x (1 + wastage% / 100))
Source: WIA/NGPP installation guidelines
Key Assumptions
- Standard American double roll: 27 inches (686 mm) wide x 27 sq ft usable coverage (approximately 20.5 ft / 6.25 m long) — US wallpaper industry standard
- US wallpaper is sold in double rolls but priced per single roll — US wallpaper industry convention
- Default 10% wastage for trimming and alignment — WIA/NGPP installation guidelines
- Pattern repeat of 0 indicates a plain wallpaper with no matching required — WIA/NGPP installation guidelines