Tide Mark on Walls
A horizontal line of discolouration or salt deposits running along the base of ground floor walls.
What Is Causing This?
- 1Rising damp bringing salts up through the masonry
- 2Evaporation leaving salt deposits at the damp front
- 3Failed DPC allowing ground moisture to wick up the wall
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 damp specialist will install a new DPC, hack off contaminated plaster, apply salt-inhibiting render, and re-skim the wall before it is redecorated.
How Much Will It Cost?
National average estimate
Labour: £577 – £1,887 | Materials: £370 – £1,475
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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:
How to Prevent This
Address rising damp at the source rather than covering the marks with paint. Use specialist renovation plaster on walls with salt contamination.
Related Problems
Damp and discolouration on ground floor walls, typically up to about one metre from the floor, with a tide mark.
White, powdery, or crystalline deposits appearing on the surface of internal or external walls.
A persistent damp area at the base of an internal wall, often with peeling paint or a musty smell.
Other Damp Proofing Specialist Problems
Damp and discolouration on ground floor walls, typically up to about one metre from the floor, with a tide mark.
A persistent damp area at the base of an internal wall, often with peeling paint or a musty smell.
A persistent damp, musty, or earthy smell throughout the house or in specific rooms.
Basement walls that are visibly wet, with water seeping through or condensation forming on cold surfaces.