I had calculated the water at about 1.8psi at about 4' deep so I wasn't concerned about the water crushing it, more concerded about kids jumping in off deck and landing on their heels hard. Not sure if that would dent it.
It looks like the foamular product from Owens Corning is what I'm looking for. I'll call around tomorrow. Thanks for your input. Ltvanloon.
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