Insulating radon-mitigated crawlspace floor
I finally have solve the radon problem in my house and sitting pretty with 0.8 average. Also very happy that formerly “unvented yet might as well be”, dirty, and damp space is now so clean, I only walk in my socks there.
That all said, walls I am insulating with polyiso (two layers of 1.5″), rim joist I am going to spray with closed cell, when space becomes warm enough. But it leaves the floor uninsulated.
Since there is a large hump in the middle of the crawlspace, there isn’t really a sane way to put down XPS or EPS and pour ratslab. Is there another option to insulate the floor? Is there something like sealed fiberglass in poly bags I can lay down or anything else?
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BTW, I am in zone 5
Apollo,
If I were you, I wouldn't bother to insulate the floor.
But if you really wanted to, and price were no object, I suppose you could try to find a spray foam contractor willing to install closed-cell spray foam on the floor. Once the foam was cured, you could buy another one of those clean swimming-pool liners so you could walk down there in your stocking feet.
There is about 5 degree difference from full basement on the other side of the wall (it has two former windows connecting it, for ventilation), hence why thought of insulating the floor came to mind.
Spraying closed cell on that much of the surface is definitely cost prohibitive.