How to tank a cellar – a step by step guide

Cellars are fantastic spaces that are, unfortunately, often underused because they are prone to damp. If you’re looking to create more usable space in your home, then why not tank your cellar? You can create a home office, storage space, games room or even your very own movie theatre!

One of the most common ways to waterproof a cellar or basement is with a cavity drain membrane, a specialist material designed to stop water penetrating through to the interior wall. When installed, it forms a barrier that channels potentially harmful water away into a sump below ground so that it can be pumped away.

1) Clear the working area

The first step to tanking your basement or cellar is to prepare the area and walls. This involves removing anything that is obstructing access to the wall or floor, such as shelves and cupboards. Our team can help you with this step if required.

2) Prepare the walls

Next, restore the walls to their original masonry by hacking off any plaster, render, paint or previous coatings, and scraping out old mortar joints and other lose debris, ensuring the walls are completely free of dust. You’ll also need to repair any cracks or holes with a fillet seal and if you have had problems with salt, it’s a good idea to apply a salt inhibitor. This is an incredibly important step as your brickwork needs to be in good enough condition to deal with the build up of water pressure.

3) Cut the damp proof membrane to size

Measure the area of wall you need to cover and cut the membrane to the correct size, floor to ceiling. 

4) Apply the product to the walls

Place the membrane against the wall as level as possible and drill 10mm holes through to the substrate wall.

5) Add quick seal plugs

The next step is to install quick seal plugs into the holes you have drilled. These provide an effective seal between the plug and the membrane.

6) Install the drainage channel

 The drainage channel is installed at the base of the channel. A drainage membrane is then placed on the floor and pushed over the drainage channel and against the wall. Strip tape is then used to seal the wall and floor together.

Call the damp experts

If this sounds a little too much or complicated for you, don’t fear! With over 30 years of experience in damp proofing properties across Dorset and Hampshire, the team at Croft is perfectly placed to assist you with basement tanking and waterproofing. To find out more about our professional basement tanking service, contact us today on 01202 737739.