Closed-Cell Spray Foam on Crawl Space Walls in Henrico, VA

The porous foundation walls on this Henrico, Virginia crawl space were left exposed, allowing moisture to seep through them and raise the relative humidity. The chalky-white efflorescence covering the crawl space walls indicates moisture infiltration. The open vents lining these walls also allowed the outside air and moisture to seep through them, which added to the overall relative humidity of the crawl space. To protect the crawl space from the outside, our installers sealed the open vents with precisely cut foam board pieces, which were placed within the vents and sealed with can foam. Then, our installers sprayed 1.5 inches of closed-cell spray foam insulation over the foundation walls. This amount of insulation has an R-10 value and will act as an air barrier and vapor retarder, protecting the crawl space from the outside air and moisture. A two-inch viewing strip is left at the top of the wall for termite inspectors.