Defects and failures

Peeling paint on internal damp walls

Sheet of painted plaster peeling away from a damp internal wall.

There is a difference between paint that has simply aged and paint that is being physically pushed off by water in the wall behind it. The second kind peels in larger sheets, often with a chalky or crumbling surface underneath, and repainting straight over it wastes both time and material.

Questions we are asked about this

Can you paint over damp patches to hide them while we sort the damp?

We would advise against it. Paint applied over an active damp patch fails again quickly and can mask the problem getting worse underneath.

How long does a wall need to dry before repainting?

It depends on how saturated the plaster was and the season, and can be weeks rather than days. We take readings rather than guess.

Do you fix the damp itself?

No, that is usually a separate trade — a roofer, damp specialist or builder depending on the cause. We can advise on what the pattern suggests and repaint once it is resolved.

How we tell the two apart

Aged, failing emulsion tends to flake in small pieces with a sound, dry plaster underneath. Damp-driven peeling comes away in bigger sections, the plaster feels soft or friable to the touch, and there is often a tide mark or discolouration at the edge of the affected area.

Moisture meter readings taken across and around the peeling zone
Source traced — rising damp, penetrating damp or condensation
Salts on the surface checked, since they point to long-term moisture history

Why the source has to be fixed first

No coating, however breathable, will hold a permanent bond to plaster that is still taking on water. If the source is a leaking gutter, a failed damp proof course or bridged cavity, that has to be addressed by the right trade before any redecoration is worth doing.

Once the wall is dry

We let affected plaster dry out properly, which can take longer than people expect, before repainting with a breathable system that will not trap any residual moisture. Badly affected plaster sometimes needs cutting out and replacing rather than painted over.

Drying time agreed honestly rather than rushed for a quick finish
Breathable finish specified once moisture readings are back to normal
Salt-affected plaster treated or replaced before recoating

How we work on this

We take moisture readings before quoting any repaint over a previously damp wall.
We will say plainly when redecoration should wait for another trade to finish work.
Affected plaster is assessed for whether it needs replacing rather than just repainting.