How to damp proof a basement

A guide to the systems used for tanking a basement.

When it comes to building a basement, top of most people’s concerns is how waterproof will my basement be? The answer is very – thanks to new technologies, making a basement watertight these days is really quite straightforward.

Damp proofing a basement is known as tanking – in effect, making the structure completely watertight, just like a fish tank. There are two main ways to do this and various factors will determine the method used, such as the age of the property, whether there is an existing cellar, and how high the water table is in the area. 

The first system is known as a mechanical, or dry, system, and is used for new basement excavations or if the area is particularly damp. With these systems, thick rubber membranes are fixed to walls and floors to create cavities through which water, which ingresses naturally from the ground, is allowed to drain away. This system works in conjunction with the installation of a pump that drains any residue water away from the house and into the nearest main drain.

Alternatively, a basement can be damp proofed using a wet system. This involves rendering a surface coating to walls and floors to create a waterproof barrier and watertight seal. There is no pump needed with this system which can reduce costs considerably. This type of system works well if there is an existing dry basement or cellar at the property.

At Cool Basements, we use several products to tank our basements, and are main installers of Delta Membrane Systems, Newton Waterproofing and Sika Waterproofing, generally regarded as the Rolls Royce of basement tanking products.

For peace of mind, we like to offer our customers a guarantee that is as watertight as our basements – the tanking products we use for damp proofing our basements come with a 20-year warranty and all of our basement construction work comes with a 10-year insurance backed guarantee.

Peter Little
The Cool Basements Company Ltd.