Radon mitigation retrofit – GreenBuildingAdvisor

The house is in EPA zone 1 for radon.

The house’s living space is 1,400 sqft with a 1,000 sqft walk out basement the basement. The basement is poured concrete slab and poured concrete walls.

There is no radon mitigation system.

I’m in the process of making this house as air tight as I can and will do a blower door test hoping to bring it below 1 ACH.

I’m considering putting 8 inches of repurposed felt faced polyiso on top of the basement slab, a vapor barrier sandwiched in the foam and a plywood floor.

Is it possible that if I placed a perforated pipe radon mitigation system in channels within the first 4″ of ridgid foam that I could create a functional above slab system? 

The vapor barrier would run across the floor and up the walls and get taped off at the top of the concrete wall which is above grade.  

This house will also have a ERV system in the house.

Thanks for any input!