The Type-C Waterproofing grade is defined by BS8102:2022 as where the structure itself provides the initial resistance against water ingress but also incorporates a drained cavity within the basement structure. The structure will permanently rely on the cavity drainage system to collect groundwater ingress through the structure and direct it to drains or a sump pump for removal.

Modern interior basement waterproofing systems that use cavity wall membrane, drainage systems and sump pumps would be classed as Type-C waterproofing.

Type-C waterproofing systems are ideal for achieving Grade 3 levels of waterproofing.

The document below was put together by the Property Care Association (PCA) to explain best practice for applying Type-C waterproofing in below ground structures. A good example of Type-C waterproofing would be a modern internal basement waterproofing system. These systems typically consist of some kind of waterproofing membrane, drainage channel and sump pump. Type-C waterproofing is defined by the British Standards Institute (BSI) code of practice BS8102:2022.


If you want expert advice on installing a Type-C waterproofing system then call Wise Basement Systems. Our qualified staff can also be contacted online using our online contact form.

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