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Sigma GPS Total Gas Barrier is a multi-layer, low density polyethylene membrane, reinforced with a polypropylene reinforcing grid with an integral aluminium foil. Sigma GPS Total Gas Barrier is specifically designed and manufactured to perform as a methane, carbon dioxide, radon ground gas, volatile organic compound and air & moisture protection system. Sigma GPS Total Gas Barrier Complies with the latest codes of practice as published by BRE, CIRIA, and BSI (BS 8485:2015). Suitable for use as gas protection for NHBC GREEN, AMBER 1 and AMBER 2 site characterisations.

Installation –

Sigma GPS Total Gas Barrier should be installed in accordance with the product installation guidelines, and in accordance with BS 8485:2015. For NHBC AMBER 2 and BS 8485:2105 situations, the installed system will need independent validation to CIRIA C735 to comply with the latest guidance from NHBC and British Standards.

Jointing and Sealing –

It is recommended Sigma GPS Total Gas Barrier be heat welded where possible, with welding carried out by competent personnel with suitable qualifications in accordance with best practice , and guidance contained within BS 8485:2015. Sigma GPS Total Gas Barrier should be overlapped by at least 100mm . If taping joints, only suitable tape must be used, ensuring application with a silicone roller to remove trapped air. Sigma GPS pre-formed details, or Self-Adhesive Gas Membrane are available for sealing around protuberances.

System Components –

A wide range of accessories are available for use with GPS Total Gas Barrier, including:

  • Sigma GPS Gas Tape
  • Sigma GPS GRM Self Adhesive Membrane
  • Sigma GPS Prime
  • Sigma GPS Top Hats and Preformed corner cloaks
  • Sigma GPS Protection Fleece
  • Sigma GPS Geo-Vent Void Former (25/40mm)