Symptoms
- Raised bubble or pocket under the wallpaper surface
- Bubble may be soft (air) or feel slightly wet (moisture)
- Sometimes appears only after humidity changes
Likely causes
- CommonTrapped air during installationAir pockets can form if the paper wasn't smoothed out fully when hung.
- CommonPaste that didn't bond evenlyUneven paste application leaves spots where the paper isn't stuck down.
- PossibleMoisture getting behind the paperHumidity or a small leak can loosen paste and create a bubble over time.
What to do
- Press the bubble to feel whether it's dry air or damp.
- For a small dry bubble, make a tiny slit with a sharp blade along the pattern lines.
- Inject a small amount of wallpaper adhesive into the slit with a syringe applicator.
- Press the area flat with a seam roller or soft cloth.
- Wipe away excess adhesive immediately.
- For a damp bubble, find and fix the moisture source before repairing.
- Let dry fully and check that the area lies flat.
Tools and parts
- Sharp utility blade
- Syringe applicator
- Seam roller
Wallpaper adhesiveSearch: “wallpaper paste adhesive small tube”
When to call a pro
Call a wallpaper professional for large or repeated bubbling, especially if it points to a moisture problem behind the wall.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.