Hydrostop WSM

Hydrophilic Mastic Sealant

Product Documentation


HYDROSTOP WSM is a gun-applied mastic sealant for application where a swellable mastic is required to provide an effective watertight seal in confined applications. The hydrophilic properties of HYDROSTOP WSM display good consistency in swell rate during repeated wet/dry cycles. When it is confined by concrete it will create a positive pressure against the face of the concrete joint which will prevent the passage of water.


HYDROSTOP WSM is used as an adhesive for bonding HYDROSTOP BR to concrete substrate. It is also used as a hydrophilic sealant for providing an effective seal in difficult areas which preclude the use of the hydrophilic water stop. It is used for sealing around pre-cast segments, metal beams, service penetrations and as an effective mastic for the bonding of HYDROSTOP BR to HYDROBAR PVC WATERSTOPS.

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  • Provides an effective seal to a variety of substrates.
  • Swells in excess of 200 % to produce a water tight seal.
  • Durable performance for the life time of the structure.
  • Fast curing enabling concrete to be placed within 24 hr.
  • Good adhesion to a variety of substrates.
  • Design life at least equal to that of the structure where it is incorporated.

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