What Type Of Waterproofing?

What Type Of Waterproofing?

The Types of Waterproofing

The British Standard for Waterproofing, BS8102:2009 defines 3 “Types” of waterproofing.

Understanding the properties and the requirements of each type is crucial for the success of any basement waterproofing project.

Type A Basement Waterproofing Systems are barriers that are applied to the structure. And can be used either externally or internally.

Type A Waterproofing Barriers can be external. Pre-applied systems such as Delta DualProof are ideal for new concrete structures. The integral polyprop fleece bonds to the outside of the new concrete creating a watertight seal.

Post-applied Type A waterproofing systems such as Koster Deuxan 2c  work really well to seal the outside of ICF or blockwork retaining walls

Type A waterproofing can also be used internally. This is often used on the refurbishment of existing structures. Koster NB1 Grey fully is used to waterproof masonry walls, basement soffits and concrete slabs.

Type B Waterproofing is waterproof concrete or watertight concrete. Although an additive system can be used to provide a waterproof concrete structure. 300mm Concrete walls and slabs formed to BS EN 1992 with a maximum crack width of 0.2 can be considered waterproof. We would recommend the use of Koster Quellband to seal the below ground construction joints. This is a swelling hydrophilic waterbar that is included in the construction joint.


Type C Waterproofing is cavity drainage. Here a sealed drainage system is used internally to divert any water that enters through the basement slab of the walls into a drainage system such as a groundwater pump or, if the topography of the site allows, out to an open aspect.

Delta Channels are used to provide accessible and maintainable drainage to a Delta Sump and Pump Unit.

Delta MS500 is mechanically fixed to the walls using Delta Qwikseal Plugs, Delta MS20 is used across the basement floor slab.