Waterproofing Foundations

Phase 1: Waterproofing and Dampproofing

While beginning to plan for waterproofing and dampproofing, foundation drainage needs to be planned as well. Typically, you can use drain tile to accomplish this. You will need to provide drainage in most areas around the foundations but not where there is natural, free-draining soil. Any subsurface water needs to be drained away in order to prevent damp basements and wet floors.

Drain tile needs to be connected with a joint pipe to a storm sewer, or another outlet where the water can be drained properly. If this is not done properly, you will be left with poor drainage, which will then lead to water leaking into the basement. When laying the tile, place it on solid and undisturbed soil around the footings, and needs to be covered with a minimum of 6 in. (150 mm) of coarse, clean gravel and crushed rock.

Waterproofing Foundations

Both waterproofing and dampproofing work to combat moistures of different kind, and they both work in different ways for different parts in the house. Waterproofing is done during the house building phase to help deal with severe water problems and only needed for foundations that will be exposed to hydrostatic pressures. If you know your home will need incorporate some waterproofing, we recommend going to an expert, since qualified professionals will know best how to work with different water pressures.

Dampproofing foundations is done to control moisture in the soil that can move into the foundation, and is also done to control the movement of moisture from concrete into interior wood frames. Common approaches to dampproofing include polyethylene, sheet material, or a heavy coat of bituminous material. Any foundations that are waterproofed don’t need to be dampproofed; this is a great money saving tip since it can be easy to be over careful and do both.

Any concrete that is below grade needs to be damproofed on the exterior surface starting from the footings, all the way to the finish grade line.  Also, it is wise to check and see if the soil around the foundation is poorly drained. If this is the case, waterproofing is needed. We decided to add some additional moisture protection by also using special dense glass-fibre insulation.