Waterproofing and foundations

Inhibiting rising damp

Keeping the transition between the foundation and façade dry is not only a matter of aesthetics, but it is also important in terms of the indoor climate and prevention of moulds and fungus. Injection and capillary cuts can be effective solutions.

Natural processes

Rising damp is a natural effect due to the pressure of water present in the soil and the porosity of masonry materials. This capillary effect may lead to a water/moisture rise within the wall. This is often seen as wet and darker areas with flaking renders and salt efflorescence where the water penetrates the render. Dark areas that look like wet spots are also an indication of a high level of salts in the surface withholding the water in its salt crystals. The salt crystals grow bigger than the pores can deal with and this results in flaking renders. Rising damp can be seen inside and outside, high up on walls at connection points and at foundations, and on different substrates. To deal with this issue, a good drainage system and waterproofing is necessary. 

Injection and capillary cuts

Moulding

If there is both good drainage and waterproofing below ground, it may be necessary to perform a capillary cut in the masonry to avoid rising damp. This capillary cut can be performed by injecting a chemical agent capable of filling all the capillaries and pores in the masonry, thus stopping the rising damp. Another method is to physically cut and insert a metal sheet a few centimetres above ground. This may stop the capillary rise in the render, but not if the capillary rise is also taking place inside the masonry. Please contact your local organisation to get an overview of methods used in your area and best suited to your project.