A plain flat metal sheet is like hard sheet of paper. To add structural back bone to it without adding other material to it, manufacturers strengthen the metal roof corrugating or folding the metal sheet to make ridges and grooves. In the same way that the paper that makes up a cardboard box is strengthened by the sheet of wavy paper sandwiched between two flat layers, sheets of metal can be made stronger this way.The folding may not necessary be wavy it as it was traditionally done, ribs are also another way to strengthen the metal roof. The height of the ribs from the base metal sheet varies from one manufacturer to another, each providing different strength. For example, Rib 30 Metal Roof describes the height of the rib as 30mm from the base metal sheet. The height of the rib is useful for better spanning capability and water discharge capacity.The signature shape of ribbed metal roof is the key to its durable, yet lightweight, characteristics which make it the perfect choice for many construction projects. With Ribbed Metal This special corrugated shape adds strength to lightweight materials. This means that a lightweight metal, which may otherwise be too flimsy, can be made sturdy enough to withhold years of beating in all kinds of weather.Rib Metal Roofing are commonly used for large buildings which has long span. In many cases, due to its strength, it is also used as wall panels.Beside the ribbed profiles, Ribbed Metal Roof are further strengthen by using high tensile material.