Capillary break over footing vs. vapor barrier under footing
Many building science resources recommend installing a capillary break over the footing (between the footing and foundation wall). Is there a reason this is preferable to installing a vapor barrier (i.e. 6 mil polyethylene) under the footing, up the inside face of the footing, and overlapping with the under-slab vapor barrier?
I’m assuming the foundation wall waterproofing extends all the way down the exterior face of the footing. I’m in Cincinnati, OH, and my question applies to finished basements, unfinished basements, and conditioned crawlspaces.
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