Yesterday, I had a conversation with a friend who shared his experience with the house he rented. He mentioned that the building has rising dampness reaching up to 3 feet both inside and outside the structure.

He explained how he can’t walk barefoot on the tiles whenever it rains and how his books often get damp and eventually ruined due to the moisture.

This discussion arose while we were talking about the importance of over-site concrete, also known as the German floor or Damp proof course, in buildings.

Our homes are supposed to be where we find peace not the other way round.

Here are 5 ways to treat and prevent dampness during foundation works:

1. Install a Damp-Proof Membrane (DPM): Spread a thick, durable nylon sheet across the foundation before casting the over-site concrete.

2. Proper Damp-Proof Course (DPC): Lay a DPC layer (usually bituminous felt or special plastic) at least 150mm above ground level to stop water from rising into the walls.

3. Adequate Drainage System: Construct proper site drainage (gutters, slope, soakaways) to ensure rainwater flows away from the building.

4. Ensure Proper Site Grading and Slope: The ground around the building should slope away from the foundation to prevent surface water from accumulating and seeping into the structure.

5. Use Good Backfilling Material: Backfill with laterite or sharp sand instead of clay soil to reduce moisture retention around the foundation.

Building right from the beginning is always the best approach.

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