Why can pattern repeat increase rolls?
Matching a repeating pattern can consume material at each strip, reducing practical coverage.
MAXScanner calculator
Wallpaper Calculator — Rolls, Repeat & Waste
Estimate wallpaper rolls from wall dimensions, openings, roll coverage, pattern-repeat allowance and waste.
Whole rolls to buy
9
8 base roll(s) + 1 allowance roll(s)
Full strips
24
Matched drop
100.00 in
Drops / roll
3
Calculation
- 1. Strips = ceil(480.00 in ÷ 20.50 in) = 24
- 2. Matched drop = ceil(96.00 in ÷ 20.00 in) × 20.00 in = 100.00 in
- 3. Drops per roll = floor(396.00 in ÷ 100.00 in) = 3
- 4. Base rolls = ceil(24 ÷ 3) = 8
- 5. Purchase rolls = ceil(8 × 1.050) = 9
Full-height strip model. Openings and half-drop/offset matching are not approximated; verify those layouts separately.
Formula and worked example
Required coverage = max(wall area − openings, 0) × (1 + repeat% + waste%); rolls = ceil(required coverage ÷ roll coverage).
A 40 ft perimeter × 8 ft height gives 320 ft² gross wall area before doors, windows, repeat and waste.
Assumptions
- Roll coverage must be the usable coverage stated for the product.
- Pattern repeat is modeled as an explicit percentage allowance.
Last updated: 2026-09-16
Frequently asked questions
Should openings be subtracted?
Large openings can be subtracted; keeping small openings may provide a useful cutting allowance.