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Building in a flood plane…?

BMAArch | Posted in Energy Efficiency and Durability on

I have a project in Minnesota where the garage level (because of the flood plane) is two feet below historically high water mark. With our 3 1/2′ frost protected footings that puts the below grade foundation walls potentially below water. The home owner wants to have a heated slab for the garage/shop area, so the question is a ICF that uses expanded foam a smart choice? My understanding is that expanded foams, even though they are resistant to water, can absorb water. If thats the case what might be a better option…?

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  1. Jon_R | | #1

    Wet EPS vs wet low GWP XPS R value has some contradictory claims. I think it favors the XPS when there is constant water saturation.

    You could use a frost protected shallow foundation - no EPS as deep as in a traditional foundation design. And with some fill, there wouldn't even be EPS below flood level.

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