Damp Proofing in Cape Town

What damp proofing involves

Damp proofing covers the diagnosis and treatment of unwanted moisture in walls. The three causes a specialist will rule in or out are rising damp (groundwater wicking up from the foundation), penetrating damp (rain driven through a wall or a failed seal) and lateral damp (moisture pushing through a wall that retains soil, common on Cape Town's slopes).

Treatment depends entirely on the cause. Rising damp is treated with a chemical damp-proof course, injecting a silicone cream or fluid into the base of the wall to form a new water barrier, followed by removing the salt-contaminated plaster and re-plastering with a breathable, salt-resistant render. Penetrating damp is treated by fixing the external defect and sealing the wall.

The single biggest reason damp 'comes back' is treating the symptom (re-painting over it) without fixing the cause. A reputable damp specialist uses a moisture meter, checks ground levels and drainage, and explains which type of damp you actually have before quoting.

Signs you need damp proofing

• A tide-mark band of damp rising up to about a metre on internal walls
• Paint bubbling, plaster crumbling or a white salty crust at skirting height
• A persistent musty smell that doesn't clear with ventilation
• Skirting boards, timber floors or door frames rotting or lifting
• Cold, damp-feeling walls that never seem to dry out
• Damp on a wall that backs onto a higher garden, bank or retaining structure

Frequently asked questions