After sealing the crawl space from outside air infiltration at the vent, rim & band, sill plate, and any penetrations to the outside through the foundation wall, we install insulation. This homeowner chose to use a vinyl faced fiberglass. The insulation is installed on the walls at an R-10, the required value for crawl space encapsulations per VA building code. Insulation on the crawl space walls extends the home's thermal barrier and