Radon control and drain system for a frost-protected structural slab foundation
I am working on a project that will be PHIUS Certified. It is in Zone 6, incorporates a frost protected, structural slab (raft slab system, so no thickened edges or footings). My question is about the drain system and radon control. The lot is very level so there is no where to run a drain away from the foundation. I am trying to avoid a sump all together. The rough footprint dimensions are 28′ x 28′. The slab will be 6″ or 8″ thick, with 10″-12″ of EPS foam underneath, then 2″ of compacted fine fill with 4″-6″ of gravel under that. The soil on the site is HeB, sandy loam.
How can I (or is it possible to) provide necessary drainage without a sump?
Can I include radon control in the same system?
Where would the bottom of the drain be? At the bottom of the slab, foam, gravel?
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