Precast sandwich panels provide a superior energy-efficient solution for exterior walling, whilst also being durable and fire resistant. Precast sandwich panels are typically made of an external concrete layer (non-loadbearing), an insulation layer and an internal concrete layer (loadbearing). These 3 layers are then connected using connectors that are placed during casting. The sandwich panel can be used as the entire wall structure (internal and external) with no need to plaster line internally (due to their high quality) to maximise thermal mass benefits. A range of external finishes is available.