Closed-cell extruded polystyrene (XPS) with a minimum compressive strength of 40 psi, produced with a blowing agent blend for GWP of less than 50. Designed for high-load applications such as high load floor and roofing systems, ice rinks, roadways as well as plaza and parking decks. It has high water resistance & an R-value of 5.0 per inch. It retains its insulating properties over time.