Diasen Watstop

Where to use it 

Diasen Watstop tanking plaster can be applied directly to a range of surfaces both internally and externally to make it waterproof. It is suitable for use in new-builds and refurbishment (retrofit) projects where the infiltration of rising damp or moisture from walls that are in contact with the ground needs to be controlled.

Watstop can be used if the surface being treated has a moisture content of upto 4%. There must be no water seeping through the surface at the time of installation. Any leaks causing water penetration must be diagnosed and fixed by a damp proof specialist before application of Watstop.  Alternatively, in warmer weather, when the underground water level has decreased sufficiently so that no water can seep through, Watstop can then be applied.

As for any internal wall insulation system, for optimal performance and longevity, it is crucial to evaluate the suitability of the wall and rectify any problems before installation begins. Please read our guide: “How to prepare traditional solid walls for IWI Installation” to ensure you achieve the best results.

What it does

Watstop is most commonly used internally on walls and floors, that are affected by rising damp. Due to the materials composition it works as a damp proof membrane, vapour barrier and primer for the wall or floor being treated. Even when applied only a few millimetres thick, Watstop blocks the penetration of moisture into a building.

Watstop provides the perfect waterproofing solution for basements, and underground rooms that have water trying to penetrate the building from the opposite side of the wall (negative hydraulic thrust). This is the kind of water infiltration that can lift paint or other less effective waterproofing treatments off the wall. Watstop can also be applied on the outside of exterior walls to prevent water ingress and contain water externally so it can’t enter the building (positive hydraulic thrust).

How it works 

Watstop is a fibre-reinforced epoxy-cement resin which is used against rising damp and water infiltration. It is a three-part epoxy resin which is comprised of an epoxy mortar, catalyst and cement compound. Once mixed, it remains workable for two hours so we recommend you only mix up as much material as you need. 

Coverage will depend on the intended use and applied thickness. Used as a vapour barrier the coverage is 0.6kg per m², whereas for a rising damp solution this will be 1.0kg per m² and as an underground waterproofing solution this will be 2.0kg per m².

Why we love it 

Thanks to the epoxy resin used, Watstop guarantees its performance even at low thicknesses. Watstop can be applied both internally and externally on floors and walls, on any type of surface with upto 4% moisture content with no seeping water.

With Watstop’s simple application method, either brush, roller or spatula can be used. Depending on the size of the area and thickness being applied; an airless sprayer can be used to cover large areas quickly. Watstop can be applied all year round in temperatures ranging from 5° C to 35° C.