A structural insulated panel (SIP), is a sandwich panel used in the building construction. SIP consists of an rigid insulating layer between two layers of structural board, used as a building material. The board can be the metal, plywood, and cement sheet or typically oriented strand board (OSB). Either expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), or polyurethane foam is used as the core.
SIP section is similar to the I-shaped sections. The rigid insulation core of the SIP is like a web and the surrounding sheets act like flanges. SIPs have the features of various building components, such as studs, thermal insulation, vapor barrier, and air barrier. They can be used for many different applications, such as exterior wall, roof, floor and foundation systems.