Noun: XPS, or extruded polystyrene, is closed cell insulation commonly used in remodeling and new construction applications.
XPS (extruded polystyrene) is closed cell insulation used in remodeling and new construction. XPS is typically available in flat, rectangular boards due to limitations in the manufacturing process.
XPS provides increased rigidity, making it suitable for use on roofs, below grade, below slab, and other applications.
Popular brands of XPS insulation are recognizable by their color: blue from Dow, pink from Owens Corning, green from Kingspan, etc.