How the wallpaper calculator works
Wallpaper is hung in vertical strips called drops. The calculator works out how many full-height drops you can cut from one roll, and how many drops you need to go round the room:
Drops per standard roll (10.05m)
| Wall height | No repeat | 53cm repeat | 64cm repeat |
|---|---|---|---|
| 2.3m | 4 | 3 | 3 |
| 2.4m | 4 | 3 | 3 |
| 2.6m | 3 | 3 | 3 |
| 3.0m | 3 | 2 | 2 |
Wallpapering tips
- Check every roll has the same batch number before you start.
- Hang a plumb line or use a laser level for the first drop. Walls and corners are rarely straight.
- Prepare walls with size (diluted paste) or a primer, and use lining paper on poor walls.
- Paste-the-wall papers are quicker; paste-the-paper types need to soak for the time on the label.
- One tub or packet of paste normally covers about 5 rolls. Check the label for heavy vinyls.
Worked example: a 4m × 3m bedroom
The walls run 2 × (4 + 3) = 14m round the room. At 2.4m high, each drop is 2.4m plus 10cm for trimming = 2.5m, so a 10.05m standard roll gives 4 drops. 14m ÷ 0.53m = 26.4, so you need 27 drops, which is 7 rolls, plus 1 spare = 8 rolls and 2 packs of paste.
Choose a paper with a 53cm pattern repeat and each drop grows to about 3m, so only 3 drops fit on a roll. The same room now needs 10 rolls. Pattern repeat makes a big difference, so always check it on the label before you order. Papering one 3.5m feature wall in the same plain paper takes just 2 rolls, plus a spare.
Choosing the paper
- Non-woven (paste-the-wall): the easiest to hang and to strip later. Paste goes on the wall and the dry paper goes straight up.
- Vinyl: tougher and wipeable, good for kitchens, hallways and children's rooms. Use the heavy-duty paste the maker recommends.
- Lining paper: hides minor cracks and uneven plaster. Hang it horizontally ("cross-lining") under good-quality paper so the joints never line up.
Where to start and finish
Start your first drop next to the main window and work away from it in both directions, so joints are less visible in the light. Finish in the least noticeable corner, often behind the door, where the pattern match will break. For a feature wall, centre the first drop (or a strong motif) on the wall or chimney breast and work outwards.
Turn the power off before papering round switches and sockets. Loosen the faceplates, trim the paper and tuck it behind them.
Common wallpapering mistakes
- Mixed batches. Rolls from different batches can be a visibly different shade. Check every label before cutting.
- No spare roll. Running out halfway and finding the batch has sold out is a common and costly problem.
- Papering over new plaster. Fresh plaster must be fully dry and sealed with size or primer first, or the paper won't stick evenly.
- Trusting corners to be straight. Wrap only a few millimetres round an internal corner, then start the next drop on a fresh plumb line.
Painting the other walls or the ceiling? Use the paint calculator, then the skirting board calculator to finish. The redecorating planner puts paint, paper, skirting and flooring in one list.