Passive Gas Venting

With an increase in ‘brown field’ development and regeneration, engineers are experiencing a growing challenge to build on contaminated land.

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Passive Gas Venting

Passive gas venting solutions are frequently specified by consulting engineers and passive gas venting system suppliers / installers for use below the footprint of new developments, especially on brown field sites. These passive gas venting systems are designed to effectively facilitate the collection and dispersion of the ground gasses.

One of the key components within the passive gas venting system is the geocomposite, which can use a 25mm or 40mm deep HDPE drainage board with a non-woven filter geotextile bonded to the top of the cuspate studs (25mm deep is the most commonly specified under BS8485 regulation).

Our FC25 and FC40 Gas Venting geocomposites provide high gas flow capacity and compressive strength, are UV stabilized, lightweight and easy to install within the passive gas venting system (by others).

We also manufacture a specific gas membrane protection geotextile that is compatible with our Gas Venting geocomposites (HPS geotextile range)

Key Benefits

  • Suitable for single strip installation (partial cover) or can be butted together to create full blanket coverage of the foundation footprint
  • Flexible and easy to install with 50m roll lengths to reduce installation time
  • The cuspate studs design is optimized to provide high compressive core strength, i.e. FC25 geocomposite provides 300kPa (30 ton/m²) compressive strength
  • Shallow depth of geocomposite (FC25) allows for a ‘reduced dig depth’ compared with traditional clean stone aggregate layer
  • Filter geotextile 100mm wider than the drainage board to enable easy lapping
  • Compatible with wide range of fixtures and fittings (by others)

FC25 Gas Venting
gas venting

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