Painters and decorators
How to calculate wallpaper rolls with a pattern repeat
Count full-height drops on each wall, allowing for the width of the chosen roll. Then allow enough length per drop for trimming and the pattern match, count the complete drops each roll can supply, and round the final roll total up. The example below uses a straight match. A half-drop or other offset design needs its own matching method before you use the number in a quote.
Sources: [1] Cole & Son (accessed 2026-09-21); [4] Graham & Brown (accessed 2026-09-21).
Check the room and the roll
Measure each wall width and the full drop height. Read the chosen roll's width, length, vertical repeat and match type from its product information or label. Those details vary by design, so check the actual paper again before ordering.
Sources: [2] Cole & Son (accessed 2026-09-21).
For a concrete illustration, Dunelm lists its Cane Panel Panelling Wallpaper as a 0.52 m-wide, 10.05 m-long roll with a 0.53 m straight-match repeat. These are the listed specifications for that product, not standard dimensions for all wallpaper.
Sources: [6] Dunelm (accessed 2026-09-21).
The room used below is hypothetical: 3.6 m by 3.0 m, with four walls to paper at 2.4 m high. It assumes a combined 0.10 m for trimming above and below each drop and does not deduct doors or windows. Set your own trim allowance for the room and the chosen paper.
Sources: [5] Graham & Brown (accessed 2026-09-21); [1] Cole & Son (accessed 2026-09-21).
Count drops on each wall
Divide each wall's width by the roll width and round up on that wall before adding the counts. Counting wall by wall avoids assuming that a part-width offcut at one corner covers the next wall.
Sources: [1] Cole & Son (accessed 2026-09-21).
| Wall width | Whole drops per wall | Number of walls | Drops for those walls |
|---|---|---|---|
| 3.6 m | 7 | 2 | 14 |
| 3.0 m | 6 | 2 | 12 |
| All four walls | Not applicable | 4 | 26 |
Sources: [1] Cole & Son (accessed 2026-09-21); [6] Dunelm (accessed 2026-09-21).
For the 3.6 m walls, 3.6 ÷ 0.52 is about 6.92, so each needs 7 drops. For the 3.0 m walls, 3.0 ÷ 0.52 is about 5.77, so each needs 6. The four wall counts add to 26 full-height drops before any special cuts.
Sources: [1] Cole & Son (accessed 2026-09-21); [6] Dunelm (accessed 2026-09-21).
Allow for the straight pattern repeat
The repeat is the vertical distance before the same point in a pattern appears again. On a straight match, adjacent strips line up at the same height. Allow length for trimming as well as the wall height before setting the planned cut length.
Sources: [3] Graham & Brown (accessed 2026-09-21); [4] Graham & Brown (accessed 2026-09-21); [5] Graham & Brown (accessed 2026-09-21).
In this example, 2.4 m height plus the assumed 0.10 m total trim gives a 2.50 m minimum length before matching the pattern.
Sources: [5] Graham & Brown (accessed 2026-09-21).
The listed straight repeat is 0.53 m. Five complete repeats span 2.65 m, enough to cover that assumed 2.50 m minimum. Use 2.65 m as the planned length of each full drop in this illustration. Check how the design starts on the actual roll before cutting.
Sources: [6] Dunelm (accessed 2026-09-21); [4] Graham & Brown (accessed 2026-09-21).
Convert complete drops into rolls
Divide roll length by the planned drop length and count only complete drops. Here, 10.05 m ÷ 2.65 m gives 3 complete drops per roll; the remainder is too short for another full-height drop on these assumptions.
Sources: [1] Cole & Son (accessed 2026-09-21); [6] Dunelm (accessed 2026-09-21).
With 26 full-height drops needed and 3 complete drops from each roll, round 26 ÷ 3 up to 9 whole rolls. That is the illustrative straight-match count before any additional contingency, not a quantity guaranteed for a measured job.
Sources: [1] Cole & Son (accessed 2026-09-21); [6] Dunelm (accessed 2026-09-21).
Check the quantity before it goes into the quote
If the paper has a half-drop or another offset match, adjacent drops meet at a different vertical point. A larger repeat or half-drop can use more paper than this straight-match estimate. Follow the chosen design's matching instructions or calculator and recalculate the yield.
Sources: [1] Cole & Son (accessed 2026-09-21); [4] Graham & Brown (accessed 2026-09-21); [2] Cole & Son (accessed 2026-09-21).
Confirm the measured walls, any opening or special cut, the roll specification, and how much spare paper the job calls for. When ordering rolls for one continuous area, check that the batch numbers match to reduce the risk of a visible colour difference between rolls.
Sources: [2] Cole & Son (accessed 2026-09-21); [1] Cole & Son (accessed 2026-09-21).