Radon, drain tile, vapor retarder
Here’s what I have.. 1966 rancher In northern Maryland
Full basement with perimeter drain tile system leading to two sump pumps. One pump collecting the front section and the other collecting the rear respectively. Planning to finish the basement with 2×4 walls.
Home has been tested for radon and exceeds the EPA recommended level of 4 pCi/L. Our latest 3 day test was 15.6 PCI/L.
Radon Contractor recommends a single exhaust pipe that taps into both sump pits with and upgraded fan.
Obviously a drain tile system, due to its nature can act as a super highway for radon entering the home. The Radon contractor also recommends a Vapor barrier on the basement foundation walls that is tucked inside the exposed drainage system and Air sealed at the top. This would create the necessary vacuum effect needed for the radon system to function properly.
To me this sounds appealing because i believe that it will also assist in keeping the basement dry. Any moisture that makes its way through the block foundation would remain behind the vapor barrier, be forced into the drainage system thus keeping basement area dry.
My question is basically does this system make sense?
If so, what type of vapor barrier would be best suited for my needs?
Also, as i have intentions to finish the basement… with this system mentioned above, i would then frame with 2×4 walls and attempt to install airtight drywall.
Is this the best way to go or am i missing something? My concern is moisture trapped behind the wall causing problems in the future.
I also know many people line there foundation walls with rigid foam. Would standing the rigid foam off the foundation wall accomplish the same thing?
I know this is a lot, but any help would be appreciated.
Thank you all.
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