Designing Home Radon Mitigation Systems
Something I learned about in the LEED for Homes Kick-Off Meeting earlier this month that I had very little prior knowledge about was Radon and how to mitigate it. Radon, which is a radioactive gas that comes about from the natural decay of uranium that is found in nearly all soils, will move up through the ground and into homes through cracks and other holes in the foundation trapping radon inside the home where it can build up and ultimately result in serious health hazards for occupants such as lung cancer. The bad news for those of us in Cincinnati is that we happen to live in a county, which according to the EPA, has the highest potential for Radon (Zone 1) anywhere in the country. The good news is that mitigating Radon is simple and inexpensive to implement in new home construction, which is something I have since revised the drawings to incorporate into the design of the Oakley Home 2.0 project (which is also a requirement for LEED for Homes Certification in Radon Zone 1 areas like Cincinnati).
The radon mitigation system as it now exists in the Oakley Home 2.0 design, consists of a 4" diameter PVC pipe that is tied into the foundation drain-tile loop (which is also connected to the sump-pump), runs vertically through the interior wall framing, and ultimately vents out the roof above. To further aid in ventilation efforts in the event that radon is detected, a junction box is to be roughed-in in the attic space near the radon vent pipe to provide power for the future installation of a special radon ventilation fan. The building sections below show the radon vent pipe routing from the footing drain up through the attic and out the roof for reference.