The Sika® Cavity Drainage System is a water management system designed to control and manage water after it has penetrated the structure. Using high density polyethylene cavity drainage membranes, the system directs water safely into a drainage channel and collection sump before being discharged from the building via a pump. Suitable for both above and below ground applications, the Sika® Cavity Drainage System provides reliable protection against water ingress in basements and cellars.
Advantages of the Sika® Cavity Drainage System
- Controls and manages water ingress
- Suitable for substrates that do not have the strength to resist stresses caused by water pressure
- Accommodates minor structural movementsMinimal surface preparation required prior to installation
- High density polyethylene membranes provide durable and reliable water management
- Acts as an effective vapour barrier
- Suitable for use in basements and cellars on walls and floors
- Allows walls to be dry lined or plastered and floors to be screeded after installation
- Suitable for above and below ground applications
- Can be used to Grades 1, 2 or 3 according to BS 8102:2009
- Suitable for high water table according to BS 8102:2009
Components of the Sika® Cavity Drainage System
Wall membrane
Floor membrane
Anti-lime coating
Sump and pump system
Wall membrane
The wall membrane allows any water ingress to flow down to the perimeter channel. Sika® Standard Drainage Membrane is typically used for the wall membrane.
Floor membrane
The floor membrane allows water to flow into the perimeter channel. Sika® HD drainage membrane is typically used for the floor membrane due to its higher void volume and height, which allows for floor tolerance.
Anti-lime coating
Before a Sika® cavity drain membrane is laid or fitted on to floors or walls constructed of new concrete, the concrete surface should be treated with Sika® Cavity Drain Anti-Lime Coating to reduce the risk of leaching of free lime or mineral salts to avoid the obstruction of the drainage system.
Sump and pump system
The sump and pump chamber pumps water out of the building. Sika® Pump Pro Battery Back up system is comprised of a polyethylene tank, locking access cover, powerful submersible pump and 24V backup pump. It is specially designed for the removal of groundwater from basement cavity drainage membrane systems.
Our Range of Cavity Drainage System Products
CAD drawings of the Sika® Cavity Drainage System are free to download as PDFs
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FAQ
A cavity drainage system is a Type C waterproofing method that manages water entering a basement or below-ground structure by allowing it to flow behind a dimpled membrane applied to internal walls and floors. The water is directed into perimeter drainage channels, collected in a sump chamber and then pumped safely away, keeping the interior space dry and protected.
The system uses the Sika® Standard Drainage Membrane on the walls to direct water downwards and the Sika® HD Drainage Membrane on the floor to guide the water into perimeter channels. From there, it’s collected in a sump chamber, then discharged by the Sika® Pump Pro Battery Back Up.
The Sika® Cavity Drainage System is suitable for concrete, brick, stone or masonry surfaces.
The Sika® Cavity Drainage System is typically used for waterproofing the walls and floors of basements and cellars.
The Sika® Cavity Drainage System offers several key benefits:
- 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