Combi-Seal Plus

VOC-Resistant Waterproof Membrane


COMBI-SEAL PLUS comprises of a high-density polyethylene membrane (HDPE) and non-woven, geotextile, cross-laminated to produce a durable, pre-applied membrane which will resist hydrocarbons, VOCs, ground gases and water. The membrane utilises PREMCRETE APAN technology to produce a membrane which will effectively resist water pressure, gases and VOCs from within the ground.

The composite membrane will restrict gas vapour transmission to less than 40ml/day/M2 in accordance with BS 8485:2015+A1:2019. COMBI-SEAL PLUS is a highly chemical-resistant membrane which ensures that the integrity of the membrane is secure even in the presence of aggressive chemicals. The textured profile of the membrane ensures an integral bond to the structure to which it is applied.


COMBI-SEAL PLUS is a pre-applied VOC-resistant waterproof membrane for basement construction, lift pits, concrete retaining walls and other structures which extend below ground where resistance to hydrocarbons, ground gases and water is required. COMBI-SEAL PLUS may also be used to protect ground floor slabs, particularly where a good integral bond is required to the underside of the concrete slab or where a clay heave board has been installed. COMBI-SEAL PLUS achieves two points when correctly installed in accordance with table 7 of  BS 8485:2015+A1:2019.

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  • Resistant to a wide range of chemicals.
  • APAN waterproofing technology.
  • Forms strong adhesive bond to freshly placed concrete.
  • Lightweight but robust membrane.
  • High tear resistance.

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