Sika® Cavity Drainage System creates a water management system to control water after it has penetrated the structure. Utilising a high density polyethylene internal drainage membrane, the system is installed, loose laid in flooring applications and attached to the wall with surface plugs in vertical installations.

The system directs penetrating water into a drainage system and a collection sump before using a pump to discharge water from the building. A cavity drain provides protection from the ingress of water. Suitable for above and below ground usage.

The membranes are fixed to the walls using special plugs with minimum surface preparation required to the substrate. Once the membrane has been fitted, wall surfaces can be dry lined or plastered and the floors can be screeded.

Typical applications include:

  • Walls and floors of basements
  • Cellars



  • Can be used where the substrate does not have the strength to resist stresses caused by water pressure
  • Can accommodate minor movements within the structure
  • Limited surface preparation required
  • Acts as a vapour barrier
  • Can be used to grades 1-3 according to BS 8102:2009
  • Suitable for high water table according to BS 8102:2009

Regular maintenance of the system including pumps is required, therefore the design of the structure should include access for maintenance.