Protection against radon

Radon – the invisible danger from the ground

Radon is invisible, odourless and tasteless. But its radioactive decomposition products are dangerous: If the concentration  of radon in an inhabited building is too high, it can build up in the lungs and lead to lung cancer. In simple terms the  situation can be described as follows: «There are laws but no-one pays any attention to them». Radon and/or its  decomposition products are a ticking time bomb for owners and tenants.


Conclusion for responsible builders and owners

Radon causes lung cancer and is found everywhere in the ground. No two houses are the same and a measurement is  necessary in order to be establish the facts. Building measures can resolve the radon problem and safeguard the value of a property.


1. Radon-proof construction measures
  • Seal all cracks and joints in the floors and walls that are in direct contact with the soil or ground below
  • Seal all the conduits for wiring
  • Install a radon-proof division between the inhabited and the uninhabited areas
  • Floor slabs instead of strip foundations
  • Structural sealing
  • Do not use natural cellar floors
2. «Collect» radon and extract it
  • Collect radon in the room affected and extract it (reactive)
  • Drainage under the cellar and / or floor slabs (active)
  • Prevent exposure by collecting the radon in so-called «radon wells» in the earth (active)


Sisalex 871, radon barrier

Radon permeability 2.3 × 10-12 m2s-1
Radon permeability level 7.2 × 10-9 ms-1
Weight 363 g / m2

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