Damp Penetrating Through Wall
Damp patches appearing on inside walls, particularly after rain, often with a musty smell.
What Is Causing This?
- 1Cracked or missing pointing allowing rain through
- 2Blocked cavity allowing water to bridge to the inner wall
- 3Failed or missing render on the exterior
How Urgent Is This?
This should be fixed in the coming weeks. Leaving it may allow the problem to worsen and cost more to repair.
What Needs to Be Done
A builder will identify where water is entering, repair external pointing or render, and clear any cavity wall debris. Internal walls may need drying out and replastering.
How Much Will It Cost?
National average estimate
Labour: £3,325 – £8,250 | Materials: £2,300 – £6,700
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Ask a QuestionPlanning Permission Guidance
Some fixes for this problem may require planning permission or building regulations approval. Check if your project needs permission:
Generally permitted under Part 1, Class A of the GPDO. Standard permitted development allows a maximum projection of 3m ...
Garage ConversionGenerally permitted as an internal alteration that does not enlarge the building. Replacing the garage door with a windo...
Basement ConversionInternal works to convert an existing basement or cellar are generally permitted as internal alterations. However, excav...
How to Prevent This
Maintain external pointing and render. Keep gutters and downpipes clear. Ensure ground levels outside are below the damp proof course.
Related Problems
The mortar between bricks is cracking, crumbling, or falling out, leaving gaps in the brickwork.
Damp and discolouration on ground floor walls, typically up to about one metre from the floor, with a tide mark.
A persistent discoloured patch on an interior wall, often yellowish or brownish, that may feel damp to the touch.
Damp patches visible on internal walls that correspond to areas of external render, especially after rain.
Other Builder Problems
A visible crack running through the outside wall of your property, which may be widening over time.
An exterior or interior wall that bulges or leans outward, visible when looking along its length.
Diagonal cracks appearing around windows and doors, doors sticking, and visible sinking on one side of the building.
The mortar between bricks is cracking, crumbling, or falling out, leaving gaps in the brickwork.