A method of forming a composite wall (1), the method comprising the step of assembling a frame including a generally upright spaced a stud (3) (2), the majority of the cladding sheet (4) disposing a plurality of outer cladding sheet on general framework horizontally to span across the two or three or more, the thin plate (4) in abutting relationship substantially continuously skeleton studs fixed to, and forming a generally substratum on the plane for the walls, and a step of applying a surface undercoat comprising a substantially uniform mesh muscle (11) on the substrate, thereby supplements method for forming a specific internal rendering, structural wall with the appearance of primed masonry without the need for bracing or reinforcement.