R-value for floor over uninsulated crawlspace?
There are standard recommendations for high-performance R-values in homes, from the ground up -- R-40 for walls, for example, but typically much less for slabs (not going to enter that controversy by naming a number).
For various reasons, I'm considering building over an uninsulated crawlspace. What would you recommend as a rule-of-thumb R-value for a high-performance home, for the floor system, in this case? Since it won't be thermally buffered the way a slab would be, I'm thinking it should be closer to R-40 than, say R-10. But doing something less than R-40 would be preferable due to the complications of a floor system with that much insulation. Thoughts?
Posted Dec 8, 2009 12:44 AM ET
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