How to Fix Bubbles and Blisters in Wallpaper
Why most bubbles disappear on their own, how to fix the ones that do not, and the difference between a bubble and a dry patch of wall
Wait forty-eight hours before you touch a bubble. Most close on their own as the paper dries and shrinks back onto the wall. For one still there after two days: slit it along a line in the pattern with a fresh blade, work a little paste behind it with a fine brush or a syringe, press it back from the outside in, and roll it gently.
Why bubbles happen
- Air trapped while hanging, the commonest cause, and the easiest to avoid by smoothing from the centre of the length outwards rather than starting at an edge.
- Excess paste pooled under the paper rather than spread evenly.
- A dry patch on the wall where the roller missed, so the paper has nothing holding it there.
- A hollow in the wall that the paper bridged instead of being pushed into.
- Dust in one area, stopping the paste gripping.
Wait first
Damp paper expands very slightly on the wall and contracts as it dries. A wall that looks like it has chickenpox on the evening you hang it is very often perfectly flat the next morning.
Give it a full forty-eight hours in a room with the windows closed and the heating at its normal setting. Resist the urge to press bubbles down while the paste is wet: you push paste into a ridge that then has to go somewhere else.
Fixing a bubble that stays
- Choose your cut. Find a line in the design that runs through or near the bubble: a stem, an edge of a motif, a change of colour. A cut along a pattern line disappears; a cut across a plain area does not.
- Slit it with a fresh blade, a single clean cut through the paper only. Do not cut a cross or a flap.
- Get paste behind it. A fine artist's brush slid through the slit works, and so does a syringe of adhesive if you have one. You need very little.
- Press from the outside in, working the air and surplus paste towards the slit rather than away from it.
- Roll the slit closed gently with a seam roller so the two edges meet.
- Wipe immediately with a clean, slightly damp white cloth. Never scrub, and never a wet sponge.
Larger blisters
A bubble bigger than the palm of your hand usually means a dry patch of wall rather than trapped air. Slit it and feel through the opening. If the wall behind is dry and dusty, the paper is not going to stay down with a dab of paste.
Lift that section of the length carefully, paste the wall properly, and smooth it back. If the paper has already dried hard and creases as you lift it, replace the length.
Bubbles in peel and stick
Different problem, different fix. There is no paste to add and nothing to dry, so a bubble in removable paper is simply trapped air.
- While you are hanging, work air out to the nearest edge with the smoother. This is exactly what smoothing from the centre outwards is for.
- For a bubble already smoothed over, pierce it with a pin at its lowest point.
- Press the air down towards the pinhole with the smoother.
A pinhole is invisible. A slit in peel and stick tends to open up again, so use a pin rather than a blade.
Stopping it happening on the next wall
- Smooth from the centre of the length outwards and downwards, never edge first.
- Paste evenly and slightly wider than the length, with no puddles.
- Dust the wall immediately before hanging.
- Push the paper into hollows rather than across them.
- Let the room dry slowly, windows shut, heating normal.
Will wallpaper bubbles go away on their own?
Most do, within twenty-four to forty-eight hours, as the paper dries and shrinks onto the wall.
My wallpaper still has bubbles after 24 hours: is that normal?
Yes. Give it a full two days before deciding anything needs fixing.
How do I get rid of a bubble without it showing?
Cut along a line in the pattern rather than across a plain area, and close the slit with a seam roller.
Can I just push the bubble to the edge?
Only while the paste is still wet and only near an edge. On dry paper you will crease it.
What causes bubbles in the first place?
Trapped air, uneven paste, a dry patch of wall, or dust.
How do I fix bubbles in peel and stick wallpaper?
Pierce with a pin at the lowest point and smooth the air down towards the hole.