An exterior finishing system for a building is disclosed herein. The exterior finishing system may include a panel comprised of high density closed-cell foam, the panel securable to a substrate of a building. The exterior finishing system may further include a bonding layer disposed upon a surface of the panel, the bonding layer comprising water and acrylic polymer. The exterior finishing system may further include an exterior layer comprising calcium carbonate disposed upon a surface of the bonding layer. Methods of use of the exterior finishing system are also disclosed.