#Sheet metal roofing manual#

Regular ferrous alloys are the most common due to price and availability. The most common materials for corrugated iron are ferrous alloys (e.g. Many materials today undergo the corrugation process.

Industrial buildings are often built with and covered by trapezoidal sheet metal. The traditional shape of corrugated material is the round wavy style, but different dies form a variety of shapes and sizes. After the sheet metal passes through the rollers it is automatically sheared off at a desired length. In the corrugation process sheet metal is pulled off huge rolls and through rolling dies that form the corrugation. This modern process is highly automated to achieve high productivity and low costs associated with labour.

Today the corrugation process is carried out using the process of roll forming. Galvanised sheets with simple corrugations are also being gradually displaced by 55% Al-Zn coated steel or coil-painted sheets with complex profiles. Wrought iron CGI was gradually replaced by mild steel from around the 1890s, and iron CGI is no longer obtainable, but the common name has not been changed. CGI is also a common construction material for industrial buildings throughout the world. CGI is also widely used as building material in African slums and informal settlements.įor roofing purposes, the sheets are laid somewhat like tiles, with a lateral overlap of one and half corrugations, and a vertical overlap of about 150 millimetres (5.9 in), to provide for waterproofing. In Australia and New Zealand particularly it has become part of the cultural identity, and fashionable architectural use has become common. It soon became a common construction material in rural areas in the United States, Argentina, Spain, New Zealand and Australia and later India, and in Australia and Argentina also became (and remains) a common roofing material even in urban areas. It proved to be light, strong, corrosion-resistant, and easily transported, and particularly lent itself to prefabricated structures and improvisation by semi-skilled workers. It was originally made from wrought iron produced by puddling. Henry Robinson Palmer, architect and engineer to the London Dock Company, was granted a patent in 1829 for 'indented or corrugated metallic sheets'. On display at Kapunda museum, South Australia Contemporary use of corrugated galvanised iron in architecture (Australia)

#Sheet metal roofing manual#

History Early manual corrugated iron roller. Its unique properties were used in the development of countries such as Australia from the 1840s, and it is still helping developing countries today. It was and still is widely used especially in rural and military buildings such as sheds and water tanks. Normally each sheet is manufactured longer in its strong direction.ĬGI is lightweight and easily transported.

The corrugations increase the bending strength of the sheet in the direction perpendicular to the corrugations, but not parallel to them, because the steel must be stretched to bend perpendicular to the corrugations. Although it is still popularly called 'iron' in the UK, the material used is actually steel (which is iron alloyed with carbon for strength, commonly 0.3% carbon), and only the surviving vintage sheets may actually be made up of 100% iron. The galvanised sheet is viewed from below and is supported by a piece of angle iron (painted white).Ĭorrugated galvanised iron or steel, colloquially corrugated iron (near universal), wriggly tin (taken from UK military slang), pailing (in Caribbean English), corrugated sheet metal (in North America), zinc (in Cyprus and Nigeria) or custom orb / corro sheet (Australia) and occasionally abbreviated CGI is a building material composed of sheets of hot-dip galvanised mild steel, cold-rolled to produce a linear ridged pattern in them. Type of metal building material Corrugated galvanised iron roofing in Mount Lawley, Western Australia A corrugated iron church (or tin tabernacle) in Kilburn, London Typical corrugated galvanised iron appearance, with visible large flake type patterns.