Pure Basement Systems News

Basement Membranes | Egg-Box Membranes | Dimpled Membranes | Basement Tanking

Known by several different names, but what are they ? and what do they do?

Their correct name is cavity drainage membrane. They consist of dimpled sheets which create a free-drainage layer between the wall / floor surface and the inner face of the membrane. The dimples allow the membrane to “stand-off” of the wall / floor so water can travel behind.

Cavity Drainage Membranes are not a form of “Tanking”. Tanking or in more recent “Barrier” waterproofing relates to systems which hold water out of basements – in the main they are fitted outside of the basement and not inside. Barrier systems are predominantly used for new-build projects …

It’s critical that accumulated water is removed from behind these membrane systems. They are not designed to stop water from entering the fabric of the building – they offer a drainage path for the water to travel towards a suitable exit point. In addition they offer a damp resistant / vapour impermeable inner skin to the basement rooms isolating them from damp walls.

Accumulated water must be removed from the cavity drainage system by effective means – either correctly designed / installed gravity drainage or a high quality sump pump station – for further information about sump pumps go to https://www.purebasementsystems.co.uk/flooded-basement-services/home-cellar-basement-sump-pump-installation/