Crawl space solution – Joist rot and drying-in questions
Recently purchased a home in Connecticut with a completely unconditioned, vented crawl space.
No evidence of mold or rot, but some musty odor, and a huge drag on energy efficiency as a fair amount of forced air ductwork travels through the space and air seeps in through the rim joists and vents and stacks upwards into the conditioned space. Space has what I wold describe as a poorly poured rat slab (meaning you can see dirt in certain areas of the crawl that are untouched by the rat slab).
We’d obviously like to improve air quality and energy efficiency and would lean towards making this conditioned space as most seem to recommend.
Primary conundrums are these:
While there is no standing water or evidence of any significant moisture issues in the crawl there is certainly reasonable efflorescence and we don’t want to create any moisture issues by actions we take.
-The joists have no capillary barrier between them and the concrete foundation walls. If we spray foam the joists with closed cell, are we opening the door to rot?
-One provider has pitched what appears to be an impermeable rigid foam wall insulation from floor to joist once floor is encapsulated. Given efflorescence present on foundation walls, are we asking for trouble by limiting the amount of “drying-in” that will take place?
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