Waterproofing a Slab Foundation: What You Can Do
By Steve Rone
It is a common misconception to believe that only basements need robust waterproofing strategies. While the mistake is an understandable one – after all, slab foundations sit on the earth – the reality is that all foundations can develop problems with invading moisture.
Ultimately, any foundation can spring a leak, no matter whether it rests on the earth or is concealed deep beneath it.
What Are the Risks of Leaks in the Slab Foundation?
If a leak does appear, addressing it should be a top priority. It is crucial to find a quick solution because the slab foundation is where all of the electrical HVAC ducts, pipework, and plumbing components are housed.
If water is allowed to seep into this area, all of the components mentioned above could get severely damaged. The electrics could cut out; the drains might back up, and the HVAC ducts are likely to get obstructed and moldy.
In fact, even a little bit of moisture can cause significant problems because it encourages the production of mold and mildew in and around these components. If left untreated, this can very easily clog up pipes and vents.
And this is a ‘best case’ scenario. If the water moves beyond the foundation and you get water damage to the floor itself, the chance of a flood increases. Plus, floorboards can start to smell and soften as they develop mold on their undersides.
Tips for Protecting a Slab Foundation
If you are preparing to construct a new foundation, you should use the process as an opportunity to integrate a proper drainage channel. This should include drainage tiles and pipes, arranged beneath the level of the foundation itself. Then, water can be moved through this channel and on to a pump, where it can be safely redirected.
If you are looking for a way to strengthen and protect an existing foundation, you could always try external waterproofs skins or membranes. This usually takes the form of a substance applied to the outer surface of the concrete.
The waterproof ‘skin’ closes off all of the porous (and vulnerable) areas of the concrete. Essentially, it covers the foundation in a secure moisture proof container. When it makes contact with water, the moisture just rolls off and back on the earth.