Permavoid Geocellular System

The Permavoid system comprises of high strength modular cells suitable for sub-base replacement, plus components that incorporate silt/oil treatment and shallow flow controls into the system. 

It can be used in place of a traditional aggregate sub-base within trafficked pavements, providing a unique high strength, consistent structural raft in accordance with BS7533-13:2009.


The geocellular structures have a void ratio up to 95%, greatly enhancing the pavement's attenuation capacity and reducing aggregate requirements in hydraulic pavements. The system is suitable beneath asphaltic, block-paved or concrete pavements and for the full range of traffic conditions from domestic driveways to highways.


The Permavoid Geocellular System products includes biomats, rainwater diffuser units, capillary cones and more. 


To create deeper surface water management applications, Permavoid can also be integrated with the Polystorm geocellular system. 

Permavoid Features & benefits

  • Designed and tested for retention, attenuation or infiltration at shallower depths
  • Effective source control
  • Can be installed above a high water table
  • Allows water to spread across a site
  • Ideal for brownfield or contaminated sites
  • Can remove silt and hydrocarbon deposits
  • Removed the requirement for pumping stations
  • Oil interception at source, no petrol interceptors
  • Integrates with Polystorm geocellular solutions for deeper applications
  • High compressive and tensile strength under load
  • Suitable beneath both porous and non-porous surfaces
  • Reduces excavation depth and cost
  • No need for trench supports or associated plant


See Permavoid in action here.


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