Live in Alabama. Have lake house with a crawl space. Crawl space has a vapor barrier. Floor joists and subflooring for the first floor are open to the crawl space. I see differing opinions whether I can warm up the first floor wood floors in the winter by adding batt insulation under the floor joists or whether I could put foam insulation on the exposed masonry foundation and bring the vapor barrier partially up the masonry wall. Crawl space is vented and is dry. Don't want to create a moisture problem, but want to make the passage of cold air from crawl space through the subflooring to the wood floors on the first floor.