EPS as cavity fill insulation in combination with spray foam

Recently, expanded polystyrene (EPS) has been gaining popularity as a cavity fill insulation used in combination with spray foam. Due to the high cost of spray foam, contractors are cutting costs by using EPS to fill the cavity, whether in a wall, roof or sub-floor and then covering the EPS in spray foam.

In the Midwest, contractors normally use 2″ x 6″ construction in building walls, so if spray foam is used as wall insulation, six inches is required to fill the cavity. However, if a combination of EPS and spray foam is used, the cost of spray foam can be cut in half by using EPS as a cavity fill before capping the remaining space with spray foam.

In May 2012, HomeTown Building Center of Watertown, S.D. added a new office and show room building, choosing an EPS combination to insulate its steel roof deck. The project started with 1 1/2″ sheets of EPS covering 7000-sq-ft of the steel roof deck, followed by spray foam to complete the insulation. According to HomeTown staff, this combination was chosen to avoid future complications should any of the steel roof need to be repaired or replaced.

You may want to consider this combination on your next project that requires cavity fill, especially if spray foam is being specified. Your savings could be substantial! Call us at 800-658-3444 or 605-886-8084 for more information about this popular new combination.