Waterproofing 1,273 views Jul 15, 2017
Basement conversion waterproofing solution

With our cities bursting at the seams due to lack of space, older buildings and homes are continually being redeveloped to add usable space and maximise investment returns. As a result, the conversion of dank cellars and dingy basements into habitable mega-rooms or below ground offices represents a relatively pain-free way of adding space without the need for planning permission. The problem is when it comes to excavating basements, a great deal of water can often be present. But this shouldn’t be a reason to give up, especially for the installer.

Up to 95% of all untreated basements suffer water intrusion at some time, from minor damp to total flooding. When you consider that three quarters of all building failures are attributed to water ingress, the best defence is to get the specification right first time with a high performance waterproofing solution that meets and exceeds industry best practice.

The ideal below ground waterproofing solution is one that prevents water penetration entirely and guards against any future failure. Using a high performance internal tanking system, water ingress can be prevented with one relatively simple application. One solution that has a proven track record and has been successfully used for more than a 100 years is the Sika 1 Pre-bagged Waterproofing System.

This proven waterproofing solution ensures that specifiers meet the requirements of a project with just one system and it requires no ongoing maintenance.

Many homeowners and landlords come to us asking for advice on what to do with their big old, empty basements. Extending a building or moving a business can be extremely costly and stressful these days, so by installing the Sika 1 tanking system to make these damp basements into fully habitable rooms and office space is a much easier and cost-effective option with minimal disruption to the customer. 

A pre-bagged render system, Sika 1 comprises a blend of kiln dried specially graded aggregates and cements and a liquid waterproofing admixture. The admixture is mixed into the render and bonds monolithically to the prepared substrate, blocking all gaps and capillaries, providing an impregnable and invisible seal. It essentially becomes at one with the structure.

One of the big benefits with the Sika 1 system is that it can be used for so many projects. We have installed the Sika 1 system on car parks, public and private swimming pools, containment bunds, lift pits, basements, tunnels, nuclear power plants and many more. Sika 1 is the proven solution for keeping water both in and out.. 

A crucial part of installing the system is to prepare the substrates correctly and choosing the right method for the substrate.

We mainly use scabbling shanks and guns or grit blasting machines for walls and soffits. Floors are usually prepared by Von Arx machines. All areas must be fully washed down after the preparation is complete and again directly before application commences. 

The pre-bagged mortars and liquid make it easier to get the materials to where you are working and also gives you and the client the security that the mixes are consistent. 

Anyone who is a waterproofer knows how challenging it can be when you get a project that is a ‘wet one!’ Turning up to start a project when water is gushing through the substrate, breaking the hydrostatic pressure down and then finally seeing it turned into a completely dry space, is very rewarding indeed.

By Andrew Rawsthorne of Specialist UK Restorations