VB under the footer? Radon.
I’ve been wondering about radon, and just looked at the “Vapor Barriers, Radon, Basement Slabs…” blog. There, I noticed that the sub-slab vapor barrier was continuous under the footer, apparently to help keep radon out. A vapor barrier under the footer concerns me; if you ever did get water in there, it would not dry out until it, perhaps, wicked up the foundation wall, into the slab, and out. Maybe water can sit there forever and not bother anything. ?? Is a VB under the footer even necessary for radon control, if you have radon pipes under your slab and the compacted gravel around the foundation walls is continuous with the gravel under the slab? It seems that any radon under the footer would migrate through the gravel and out your vent pipe. No?
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