Al-SIP’s are a lightweight structural insulated panel (SIP) consisting of a center core of fire-retardant EPS foam sandwiched between two aluminium sheets. The cross section of a SIP resembles that of a typical I-beam, where the aluminium skins are the beam flanges and the EPS foam core is the beam web. The aluminium skins and the panel construction make the panel extremely light, yet very strong. Each panel has rolled longitudinal edges, forming a weather sealed slip/expansion joint. Not only are Al-SIP’s lightweight and strong, they have excellent thermal insulation properties and allow for quick and easy installation.