Can you use an HRV or ERV for radon removal in a dirt floor basement?
I have a part concrete and part dirt floor in basement with mildly elevated radon levels. Radon mitigator told us to use a HRV to reduce it by about 50%. Should that work? Would an ERV work and be more efficient? Any recommendations on brand, CFM?
You can use an HRV or ERV to remove radon gas in basements and crawlspaces, but given that you say your levels aren’t too high and you have a dirt floor, covering that with a radon evacuation tube below would be the cheapest and most effective way to reduce your radon gas levels. See here –
How to remove radon gas from basements and crawl spaces
Radon is escaping through the dirt floor, so for a couple of reasons I would first cover it with a poly membrane of some kind. Either simply a standard 6-mil poly vapor barrier you would see in cold climate walls, or a radon proof membrane for basement floors, but that will cost you quite a bit more money and it may not be necessary for lower levels.
How high are your levels by the way, and where do you live? If you lay a membrane down along with a passive radon stack (as you will learn about in the page above) your levels may drop significantly. A dedicated basement HRV or ERV for radon removal works fairly well when there are no other options, but as it only dilutes the existing air, you will likely find better results with source removal, as in a radon stack below a membrane. If you can I would extend that over the concrete and cover it with insulation and a wooden subfloor if you can, its most likely the concrete floor has cracks where the radon can escape.
As for brands of HRV or ERV - I would check price, efficiency, local availability and warranty to make a call on that. And you can see here for help choosing between an HRV and ERV.