Short answer
Wallpaper peels because moisture contained in the wall evaporates. This vapor creates pressure beneath the covering, making it swell and then peel away. Two causes are possible: rising damp by capillary action or water damage.
The visible symptom
The strips peel away, bubble, or lift. The covering reacts to moisture in the substrate, but on its own it does not reveal the exact cause.
Why gluing it back is not enough
If the wall remains damp, the wallpaper may peel again. Before redecorating, you need to understand whether the substrate is sound enough.
Do the marks keep coming back despite cleaning?
That is often a sign that the cause needs analysing, not just the surface.
Useful information
For the diagnosis, specify the room, the height of the peeling, the construction period, and any recent water damage.
- Close-up and wider photos
- Height of the peeling
- Context: incident, works, damp room
Frequently asked questions
Does peeling wallpaper always come from a leak?
No. Water damage is possible, but rising damp may also be the cause.