Asked & Answered: What is the expected lifetime of the expanded polystyrene (EPS) foam?


Expanded Polystyrene (EPS) is essentially inert. There have been multiple studies of EPS in the soil for 15 to 30 years demonstrating only minor degradation of the EPS foam. EPS foam is expanded using steam. It is the entrained air that provide the insulation value in the material. EPS is a plastic and aside from contact with hydrocarbons or exposure to UV from sunlight, it is relatively unaffected by other naturally degrading processes. Geofoam® placed in the ground for decades increased its compression resistance (strength). The lifespan of EPS is long, potentially unlimited. Most of the testing has involved placing