A Nissen hut is a prefabricated steel structure made from a half-cylindrical skin of corrugated steel

Corrugated galvanised iron

Corrugated galvanised iron is a building material composed of sheets of hot-dip galvanised mild steel, cold-rolled to produce a linear corrugated pattern in them...

, a variant of which (the Quonset hut

Quonset hut

A Quonset hut is a lightweight prefabricated structure of corrugated galvanized steel having a semicircular cross section. The design was based on the Nissen hut developed by the British during World War I...

) was used extensively during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

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A Nissen hut is made from a sheet of metal bent into half a cylinder

Cylinder (geometry)

A cylinder is one of the most basic curvilinear geometric shapes, the surface formed by the points at a fixed distance from a given line segment, the axis of the cylinder. The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder...

 and planted in the ground with its axis horizontal. The cross-section was not precisely semi-circular, as the bottom of the hut curved in slightly. The exterior was formed from curved corrugated steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 sheets 10 feet 6 inches by 2 feet 2 inches (3.2 × 0.7 m), laid with a two-corrugation lap at the side and a 6 inch (15 cm) overlap at the ends.