polystyrene rigid panels
Rigid thermal-insulation sheets made from closed-cell extruded polystyrene, commonly known by the Styrofoam brand.
Polystyrene rigid panels are firm sheets of thermal insulation made of closed-cell extruded polystyrene, a synthetic lightweight material. It is popularly recognized by the trademark Styrofoam, a DuPont brand. It is one of the most common materials for thermal insulation in buildings.
The material specified is extruded polystyrene, or XPS. A generic reference to polystyrene does not remove that distinction from expanded polystyrene foam.
The insulation is supplied as firm, lightweight sheets. Styrofoam is a product brand rather than the chemical name for every polystyrene material.
