Damp in a wall always has a source. Covering it with paint postpones the problem rather than solving it.
Common sources
- Leaks from pipes inside the wall
- Leaks from an adjacent bathroom or kitchen
- Failed roof waterproofing
- Rising damp from the ground
- Condensation due to poor ventilation
The right order of treatment
Find and fix the source, let the wall dry, then remove and redo damaged paint and plaster.
This is general information, not a diagnosis of your home. To identify the cause, contact us to arrange an assessment.