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Slab Thermal Break and Polished Concrete Floors

mikeferro | Posted in General Questions on

For my new house, I’m planning to wrap 2″ of foam up around the concrete slab to isolate it from the footings for a walkout basement. The problem is that I’m also planning for polished concrete floors. I’m looking for ideas on how best to hide the foam without eliminating the crucial thermal break that the foam offers. I’ve included the section for an illustration of the challenge.

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  1. Expert Member


    The two most common ways of hiding the foam are to reduce the width of your foundation wall at the top by either putting in a ledge on the interior, or canting the outside. Then the bottom plate, drywall, and trim will cover the foam. You can also taper the foam so the overhang necessary isn't as great.

    This article show the first method:

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