Take Back Your Crawlspace!
Updated: Sep 22, 2019
Don't give it up to other creatures: mold, termites, vermin! Current science indicates that crawlspaces perform better when treated like indoor spaces: mini-basements if you like! The old way was to leave vents open and insulate the floor with fiberglass batts. This allows for drastic flucuation in temperature and moisture and many openings for critters. Today's solution is to insulate the walls with fire retardant foam board (leaving a three inch gap at the top to check for termites), seal and or remove the vent openings, cover the floor, and preferably the insulated walls too, with a tight vapor barrier (see other post on this), include a sump pump and or drains to prevent flooding, and provide conditioned air to the crawlspace from your HVAC system.
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