Foam glass gravel
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Has anyone used the foam glass gravel for under slab and exterior foundation insulation? There is a plant south of Philly which supplies to Virginia. The recent Green Building Advisor article on the product mentioned R values that were 11 to 15 R per foot. I wonder what happens to the R value when water or soil enters the aggregate.
Lisa
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Replies
Do you really wonder?
The thermal conductivity goes up (and the R-value goes down), of course, just like any other insulation material that gets water saturated or filled with dirt.