Designing Basement Waterproofing Systems
Waterproofing
Basements are susceptible to the ingress of moisture and contaminants from the ground. For this reason, a waterproofing system will usually be required. Guidance on the requirements for basement waterproofing systems is given in BS 8102:2022 “Code of practice for protection of below-ground structures against water from the ground”.
The choice of waterproofing system will depend on a number of factors such as the method & type of basement construction, the depth below ground, and the proposed end use. The example designs on this website are intended to demonstrate how BS 8102:2022-compliant solutions can be achieved for some of the most common basement waterproofing scenarios.
Ventilation
In addition to dampness from the ground, basements are also commonly affected by condensation issues due to moisture-laden air within the basement structure. For this reason, the waterproofing systems described in this guide will usually need to be supplemented by mechanical ventilation. A waterproofing design specialist (see below) will be able to advise on suitable ventilation options depending on the proposed end use (e.g. car parking, document storage etc…)
Design Specialist
A waterproofing design specialist with a CSSW qualification should be consulted at the design stage. Please contact our technical department on 01403 210204 or email [email protected] for details of suitable basement design specialists in your area.
Type-A, Type-B or Type-C Waterproofing?
According to BS 8102:2022, basement waterproofing system materials fall into 3 main categories (referred to as ‘Types’).
Safeguard Basement Systems are combination Type A and C waterproofing systems. This means that there are multiple barriers to water ingress. In the unlikely event that one system should fail, there is always a supporting system to prevent water ingress.
Type A – Barrier Protection
The Drybase Tanking Range provides BS 8102-compliant Type A waterproofing.
Type C – Drained Protection
Type C waterproofing collects groundwater through a cavity membrane and cavity drainage system. The cavity membrane controls the flow of groundwater. The cavity drainage system carries it away from the basement and disposes of it away from the below-ground structure.
Drybase Flex Membrane and the Oldroyd range of Cavity Drainage Membranes provide BS 8102-compliant Type C waterproofing.
