Crawlspace Insulation
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I’m currently building an ADU on a vented crawlspace foundation. Using I – joists with 16 o.c. spacing, 11 7/8 depth. Any suggestions for insulation detail? Foam w/ batt, batt only…suggestions?
Wall assemblies are R – 26 and ceiling is R – 40. Thanks in advance.
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Replies
The way I see it a vented crawlspace is so last century.
Consider insulating the exterior wall, pouring a thin slab and conditioning the crawlspace. This keeps the crawlspace at more or less the same temp & humidity as the rest of the house. Low risk for mold and rot, no chance of pipes freezing, a good place for HVAC equipment and duct work, clean dry storage space.
In new construction I see large amounts of spray foam as a big red flag for lazy design work by someone who has no concern for the budget as there is almost always a better lower cost option if they chouse to think about solving the problems.
Walta