JOSHUA TREE, CA
Spray-On House is a 2,700 sq. ft. desert retreat being built in a remote site adjacent to Joshua Tree National State Park several miles outside of Pioneertown, California. The residence will be self-sustainable. Power is provided via a solar photovoltaic system of 5 kilowatts, other environmental friendly amenities include a water collection device, water storage tank, a generator and compost toilets.
Joshua Tree, CA
Single Family Residence
2,300 sq ft
R+D Award, Architect Magazine
Interior Design Best of Year Award
The foam application proved advantageous in this case as the foam allows for ease of transport to the remote location. The single source building system addresses the challenges of getting large quantities of building materials and numerous subcontractors to the remote desert site, thus further reducing cost and environmental impact.This home will make use of a 5 lb. per cubic foot density foam, with steel reinforcement. A reinforced steel cage of rebar was embedded within the layers of spray foam and grounded to the site via a continuous spread footing. The materials and the building form provide high thermal mass, advantageous in the arid climate. An additional exterior coating will be applied over the foam for resistance to fire and UV exposure.
Our research focused on testing and sourcing foams with adequate strength and desirable environmental data. A broad range of foams was selected from multiple suppliers with varying performance characteristics. The following pages describe each of the foams considered, with a comparison spreadsheet included. While polyurethane foams have been widely used in construction since the late 1980s, our goal of creating a standalone structure out of foam is an unprecedented application of this material. Therefore determining if a product with adequate strength is readily available was our first goal. While foams typically range in density from .5 lb. to 8 lb. per cubic foot, we eventually determined that for the prototype, a foam of 2-3 lb. density with a compressive strength of 20.6 lb. per sq. ft. was adequate (and affordable).