A lightweight concrete panel for use as an outer layer of a dwelling wall, said panel made of concrete mix of cement, sand, lightweight concrete aggregate such as polystyrene beads, superplasticiser and water, said concrete mix having a nominal density in the range of 500 to 1500 kg/m.sup.3. The panel preferably has a backing sheet of polystyrene affixed thereto. The panel is used as in a cladding and insulating veneer arrangement for a load bearing subwall formed from studs or masonry. The panels are loose fixed in vertical alignment in a horizontally and vertically extending stack of panels and retained in position by retaining clips without any bonding jointing material between the panels. A method of forming such a cladding and insulating arrangement is also disclosed.