basement waterproofing

Understanding basement waterproofing and damp proofing methods

Whether you intend to fully convert your cellar, or you simply need dry storage, damp proofing and tanking can add value to your basement. In fact, keeping your basement dry is a sensible precaution to keep your property free from potentially costly structural and damp problems.

However watertight you think your property is, water has a way of penetrating the structural envelope. Basements are obviously particularly prone to damp and condensation which can result in mould and mildew. Water can get into your basement through cracks in the wall and floor and water will enter your basement if you have poor groundwater drainage or blocked gutters – if groundwater isn’t being directed away from the foundations, then you can be in trouble. If water does start to accumulate around your foundations, hydrostatic pressure can begin to build up. And that drives moisture into any available cracks below ground, taking the path of least resistance into your basement.

Damp proofing and waterproofing your basement

Before you undertake any work on your basement, talk to a specialist. They’ll be able to advise you on the best way to tank out your conversion. Waterproofing may be as simple as adding a membrane or as complex as adding a pump and drainage system, depending on the location of your property, the type of terrain its built on and the height of the local water table.

Tanking systems create a barrier against moisture, though they don’t address the issue of where moisture is coming from. A tanking product which could be a membrane, cement or bitumen is first applied to the walls and must form a bond with the substrate to be effective. Special attention needs to be applied to any cracks and any weak structural points where pressure can build and water gain entry.

If you live in a period property, or the water table is high, a cavity drain membrane system may be used. This allows moisture to flow inside a specially created cavity which is then drained away. This depressurisation zone uses the water’s own energy to channel out. One drawback with this method is that, if head height is tight, you may find you have to dig out to make your basement conversion legal.

Tackle drainage issues

In extreme cases, you may have to consider having the soil around the foundations re-sloped and an exterior damp course installed. It’s also vital that, once your basement damp proofing and waterproofing is completed, you keep your gutters clean and clear to prevent repeat problems with wetness.

If you have an underlying problem with drainage in your basement, then you may need to have a sump pump installed. Although every property is unique, it makes sense to drain water away from your building’s foundations and a pump system is the most effective way of doing this. 

Any significant investment in your home will reap rich rewards if you make the right decisions. Get your basement tanking methods right by taking professional advice and you’ll maximise your investment.