Skip to main content
EERE » BTO » Building America » Solution Center Home » Image Gallery » The exterior walls are double walls consisting of two 2x4 stud walls set 3 inches apart to form a 10-inch-thick wall cavity that is filled with blown-in fiberglass to provide a continuous R-40 blanket of insulation around the home.

The exterior walls are double walls consisting of two 2x4 stud walls set 3 inches apart to form a 10-inch-thick wall cavity that is filled with blown-in fiberglass to provide a continuous R-40 blanket of insulation around the home.