I have nothing against the azdel product, but I'm pretty sure there there is no 50% improvement in insulation over competitors. I think it might be 50% higher than an equivalent piece of luan, which is already quite small, as compared to the foamboard or fiberglass insulation behind it. In fact, I just found a specific comparison that bears this out:
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Quote:
· 50% lighter than wood
· Offers 3x the insulation value of wood
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In reality that can't be completely accurate either because I'm sure different wood has different R values.