Structural insulated panel

A structural insulated panel, or structural insulating panel, (SIP), is a form of sandwich panel used in the construction industry. A structural insulated panel, or structural insulating panel, (SIP), is a form of sandwich panel used in the construction industry. SIP is a sandwich structured composite, consisting of an insulating layer of rigid core sandwiched between two layers of structural board, used as a building material. The board can be sheet metal, plywood, cement, magnesium oxide board (MgO) or oriented strand board (OSB), and the core can either be expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), polyisocyanurate foam, polyurethane foam, or be composite honeycomb (HSC).