Permavoid 85/150

Permavoid 85 and 150 - Product Codes: PVPP85 and PVPP150


Permavoid units are available in two depths, 85mm and 150mm. Both are used to create a geocellular interlocking system designed for shallow groundwater storage or infiltration, replacing the traditional aggregate sub-base.


The system has an exceptionally high compressive and tensile strength and bending resistance with a proprietary jointing system to create a consistent structural ‘raft’ within the pavement that is ideal for the shallow attenuation of surface water. The system can also be combined in layers using interlocking shear connectors to increase depth in 85 and 150mm increments.


Permavoid Applications

The Permavoid units are suitable for use as a stormwater attenuation and/or infiltration system. The system comprises single, interconnected cells which can be installed in the ground as part of sub-base formation. Permavoid is suitable for use in a range of applications including residential, industrial estates, car parks, sports pitches, roofs, basements, pedestrian areas and rainwater harvesting.


Permavoid Performance

The structural load bearing capacity of the Permavoid units has been tested in accordance with the following European Standard: BS 7533-13:2009. The system’s structural design life expectancy, based upon creep test data (tested according to CIRIA guidelines) is as follows; for lightly loaded areas such as car parks a design life of 50 years is achievable. For areas with prolonged HGV loading a typical design life may only be 25 years, depending on the design of the pavement surfacing and structural layers over the tank.


Permavoid Installation standard

All calculations for Permavoid units are based upon site-specific load cases, pavement construction types and thicknesses, soil cover and ground conditions and the suitability must therefore be approved for each project.


Permavoid Features & Benefits


  • High strength, high capacity, shallow, sub-base replacement system
  • Stormwater attenuation and/or infiltration system
  • Used as part of a SuDS scheme to offer water storage at shallow construction depths
  • Units are manufactured from 90% recycled polypropylene (PP)
  • 100% recyclable



Literature & Technical info