Basement and Cellar Waterproofing
(Structural Waterproofing)

Structural Waterproofing

Basement and Cellar Waterproofing (now more commonly known as structural waterproofing) involves the use of techniques and materials to prevent water from penetrating the basement or cellar of a house or building.

Creating a dry usable below ground space can be and often is one of the best decisions a client can make. In this day and age where space is at a premium, creating a dry habitable, healthy environment from an unused space has been proven to add value to a property be it Commercial or Domestic.

To advise upon the best structural waterproofing solution for your property, we will need to carry out a comprehensive survey. This will then allow us to advise on the most effective structural waterproofing solutions to incorporate into the design.

BS8102:2009 (Protection of structures against water from the ground) dictates the design criteria and specifies the performance level for the design of the system dependant on its end use.

Cavity Drain Membrane Systems

Cavity Drain Membrane provide an alternative way of waterproofing walls to the traditional cementitious basement tanking systems and when applied correctly is a flexible application with a generally longer life span than cementitious systems. A crucial part of the Type C waterproofing process is the selection of the correct Cavity Drain Membranes.

It is the most effective and reliable form of structural waterproofing in most situations. It is a requirement of British Standards that all waterproofing is maintainable and repairable. The Cavity Drain Membrane system is the only form of structural waterproofing that is easily and quickly repaired and maintained.

The system usually consists of: A drainage channel cited around the perimeter of the structure which directs any water directly to a sump and pump system. The appropriately selected membranes are affixed to the walls / soffits via waterproof fixing plugs. A loosely laid membrane is applied to the floor slab and made water tight utilising waterproofing sealing tapes at all vulnerable junctions.

Control of water penetration is handled by the appropriately installed sump and pump system. The sump and pump systems themselves have a variety of extras that can be included within the design such as alarms and battery backups. Depending upon its intended use a variety of finishes can be applied to the membranes. These range from directly applied plaster finishes, dry lining and insulated systems.

Floor finishes are also dictated by the end use but can incorporate sand and cement screeds and tongue and groove flooring. Our Surveyor will be happy to advise and guide you on your selection depending on the end use. It is an important factor that this system does require periodic maintenance in place.


Cementitious systems can be provided in various forms, from cementitious slurries to multi coat render applications.

Cementitious products are probably the easiest waterproofing materials to use. They’re readily available from suppliers of masonry products, and they’re easy to mix and apply. The chief disadvantage is that cementitious products have no give to them because cement just doesn’t stretch to any degree worth mentioning. They will stand up fine to a head of water but will tolerate almost no joint or crack movement.

Such applications require good surface preparation, which is vital to its success and may often require additional preparation to movement/construction joints. These applications are not subject to periodic maintenance programme.

If you have a basement or cellar and are thinking of converting it or if you are an architect with a structural waterproofing project, call us now! from day one you will know you have the right advice and the correct contractor on board. 


We are always looking to improve our relationship with Architects. If you have a project or just need some general advice about Structural Waterproofing, please get in touch today. We always want to help and make sure that what we are passionate about is done to the highest of standards. Get one to one advice with the number above. We are experienced in dealing with all types of waterproofing problems.