A sandwich panel is a product used for cladding the walls and roofs of buildings. Each panel consists of a core of thermal insulation material, which is covered on both sides by metal plates. Sandwich panels are not structural materials but rather materials for vertical cladding. Structural forces are transferred from the steel frame or other support to which the sandwich panels are attached.

Types of sandwich panels are mainly categorized based on the thermal insulation material used in their core. Sandwich panels with cores made of EPS (expanded polystyrene), mineral wool, and polyurethane (PIR or polyisocyanurate) are all readily available.

The materials primarily differ in their thermal insulation performance, sound insulation performance, reaction to fire, and weight.