You can tell a Diamond Steel frame from the others…because it is PURPLE! DiamondTough© Light Gauge Steel frames meet all necessary Australian Standards and are ideal for flooring, walls and roofs. For tiny homes, cabins, sheds, granny flats, factories, portable offices, garages, carports, decking. You name it. Steel is the most cost-effective long-term solution because it is so durable. It won’t warp or bend or rot. It is moisture, mould, termite and fire resistant. And, it is sustainable because it can be recycled for a different use.