How to Stop Rising Damp in Ghana

Why rising damp is so common in Ghana

Rising damp happens when moisture from the ground travels up through a wall by capillary action, the same way water climbs up a paper towel. Several conditions make it especially common in buildings across Ghana:

• Porous sandcrete blocks. Most homes are built with sandcrete blocks and cement mortar, which readily draw moisture upward from the ground.
• Missing or ineffective damp-proof courses. Many buildings were constructed without a damp-proof course (DPC), or have one that has failed or been damaged.
• Bridged damp-proof courses. Raised compound paving, added floor screeds, soil heaped against walls and plaster taken down to ground level can all let moisture bypass an existing DPC.
• Ground moisture all year round. Every building stands on ground that holds moisture, and during the rainy seasons the soil around walls stays wet for long periods. That is why rising damp affects buildings in every region of Ghana, from Accra and Tema to Kumasi and Takoradi.
• Salt-laden groundwater. Rising moisture carries dissolved salts that are left behind in the wall as the water evaporates.

Signs you have rising damp

Rising damp shows up at the base of walls, usually from floor level up to around one metre. Look for:

• Paint that bubbles, flakes or peels near the floor
• White, powdery salt deposits on the wall surface (see what causes salt on walls)
• Plaster that crumbles, sounds hollow or falls away
• A visible “tide mark” where the damp area ends
• Damp patches that are worst on ground floor walls, inside and out
• A musty smell in rooms with affected walls

For a fuller checklist, see 7 Signs of Rising Damp Every Homeowner Should Know.

Step one: confirm it really is rising damp

Not every damp wall has rising damp. Leaking pipes, faulty gutters, rain penetrating through cracks, and condensation can all cause similar marks, and each needs a different fix. Treating the wrong problem wastes money and leaves the real cause in place.

Clues that point to rising damp are damage that starts at floor level, a fairly even tide mark along the wall, and salt deposits concentrated in the lower part of the wall. Our Rising Damp Guide explains how to tell the difference, and SoAqua Solutions can carry out an assessment if you are unsure.

Why painting and replastering don’t work

The most common response to rising damp is to scrape off the damaged paint and repaint, or to hack off the plaster and replaster with ordinary sand and cement. Neither stops the moisture rising through the wall, so the damage comes back, often within months.

• Repainting covers the symptoms, but salts continue to build up behind the paint and push it off the wall. We explain this in why paint keeps peeling on the same wall.
• Waterproof or “anti-damp” paints can trap moisture inside the wall, pushing the damp higher.
• Ordinary cement plaster absorbs the salts left in the wall and begins to break down again.

To stop rising damp, you have to block the moisture inside the wall itself and then reinstate the wall with a plaster that can resist residual salts.

How to stop rising damp: the StopDamp+ method

StopDamp+ treats rising damp with a seven-stage process that creates a new damp-proof course inside the existing wall, without rebuilding it.

1. Hack Off

   Remove the damaged, salt-contaminated plaster from the affected area to expose sound masonry.

2. Drill

   Using the StopDamp+ masonry drill bit, drill holes into the visible lowest mortar course along the affected wall.

3. Remove Debris

   After drilling, use the StopDamp+ Dust Remover Tool to clear dust and loose debris from each hole. Clean, open holes, free from significant drilling residue, let StopDamp+ Injection Cream penetrate and disperse effectively within the mortar course.

4. Inject

   Using the supplied caulking gun, inject StopDamp+ Injection Cream into each prepared hole along the mortar course. The cream disperses within the mortar course to form a continuous water-repellent barrier that helps stop rising moisture.

5. BaseShield

   Apply StopDamp+ BaseShield by brush to the lower wall, from the floor level up to the injection line, to help prevent lateral moisture movement below the new damp-proof course.

6. Cure

   Leave the treated wall to cure so the barrier can establish, and allow the masonry to dry before reinstatement.

7. Replaster

   Replaster the treated wall using StopDamp+ Cement Mix, an anti-salt cement additive, mixed with Portland cement, clean sand and water as specified in the installer guide. Apply evenly to the prepared wall to achieve a smooth, salt-resistant finish.

The full sequence, including hole size and spacing, is set out in the StopDamp+ Installation Guide.

Keeping rising damp away

Once the wall is treated, a few simple habits help protect it:

• Keep compound paving and soil below the level of the damp-proof course.
• Make sure gutters, downpipes and drains carry water away from the base of the walls.
• Fix leaking pipes and taps near walls promptly.
• Use breathable finishes on treated walls rather than sealing them with impermeable coatings.
• Allow the wall time to dry out before final decoration.

Frequently asked questions