Reclaimed rigid insulation – what to look for / ask for
Hello GBA Community:
I’ve engaged a builder to build a house in Guilford, CT (Zone 5). I’m looking into exterior rigid insulation and hope to purchase reclaimed insulation from one of the regional reclaimers. The house will have hardie board siding if that is relevant.
I have few questions:
1. What should I be looking for in terms of type of foam? We are on the warm edge of Zone 5. Is EPS preferable due to permeability? Can we get away with 1 inch of polysio even with cold-value performance issues? Must it be foil-faced or will any rigid insulation do?
2. Upon inspection, what should I look out for? Upon calling reclaimers, what questions should I ask? Is there any form use that is not desirable due to its effect on the insulation?
3. Is there any type that will be faster to apply than others? (I know my builder will be concerned about time.)
4. Is it acceptable to mix and match types / sources of insulation? What are the risks? I would only do so if I cannot find enough of the same type from a reclaimer.
5. Given that a minimum thickness to the exterior insulation is required to avoid moisture issues inside the walls if we end up using batt insulation, should I be over compensating on thickness due to degradation in R-value?
6. Given that the house will be on the warm end of Zone 5 (closer to 4A), can we cheat a little on the minimum thickness/R-value required for Zone 5?
Thanks in advance (and apologies if these questions have been collected elsewhere).
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