Basement finishing/HVAC/Radon…?

[charlie74]

Hello all, since there is expertise in many areas here and my google searches haven’t turned up much I thought I’d ask;

I’m chipping away at finishing a rec room in our southeast MI basement which is a poured concrete slab with poured concrete walls. It’s a nice dry space with great potential and there are indications (plumbing roughed in etc) that it was intended to be a finished space at some point. The builders (1994) put in heating ducts in the ceiling which is great but there are no cold air returns at all. I am hoping to add some to help with even dispersal of warm air but my concern is that in our area there are elevated levels of radon.
We have a radon mitigation system installed with a sealed sump and it’s piped up above the roof line and evacuated as per code.

If I add cold air returns will I be circulating radon throughout the house via forced air or is the mitigation system in place sufficient to make this not a concern.

Thanks in advance!

C74

 

[Gliderman8]

Have you tested the space to see what the radon levels are?

 

[charlie74]

It was tested before we moved in 7 years ago and was high enough for the mitigation to be required. It wasn’t installed prior to that and at the moment I’m away from home and the paperwork. I suppose another test would be easy enough to get and see…

 

[DNK]

...If I add cold air returns will I be circulating radon throughout the house via forced air or is the mitigation system in place sufficient to make this not a concern.

Thanks in advance! C74

Or you could just install a mini split.
Costco has them now you do yourself