Hydroflow HP

Cavity Drain Membrane System

Product Documentation


HYDROFLOW HP is a cuspated HDPE drainage membrane suitable for installation on internal walls and floors. It is designed to provide a free-draining void for the collection and control of water that permeates through a concrete or masonry sub-structure. The void created by the cuspated sheet allows the water to free flow to a drainage channel or sump. HYDROFLOW HP is available in two thicknesses. The 8mm thick membrane is typically used for application to vertical substrates or for the control of light water ingress.

The 20mm membrane is typically used for application to horizontal or floor constructions or where the control of higher volumes of water ingress is a consideration. The membrane is chemical resistant and does not support bacteria and fungi growth, therefore providing an effective barrier to water for the life time of the structure to which it has been installed.


HYDROFLOW HP is used to control water ingress and create a Grade 3 environment in accordance with BS 8102/2009. Structures include habitable basements, carparks, tunnels and vaults.

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  • Rapid and easy installation to concrete and masonry substrates.
  • Minimal surface preparation required prior to installation.
  • High compressive loading stability.
  • Effective method of creating entirely dry conditions in high risk areas.

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