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Sealed crawlspace waterproofing

TractorSteve C | Posted in General Questions on

I am building  1500 sqft addition in Oklahoma that has a sealed crawlspace.  The floor will have a partial rat slab for storage and gravel with 15 mil visqueen with 3-4′ headroom.  I would like to seal the concrete both inside and out with a silicate base sealer such as RadonSeal and then coat the exterior with Barricoat R waterproofing.  The top of the footing was not sealed before the stem walls were poured.  I would prefer not to run the visqueen up the interior walls.  Would the Radon Seal be sufficient on the interior walls?  Most areas will have exterior insulation (Styrofoam and Roxul Comfort Board) with Roxul on  a few of the interior stem walls as well.  My concern is moisture coming up through the footing into the stem wall since there isn’t a capillary break.  The Radon seal says that it penetrates 4″ deep, so if it is sprayed both inside and out on an 8″ stem wall, will it meet and be sufficient?  Any advise or better product options would be much appreciated. 

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