November18, 2006: It's been about a century now since portable military structures (rigid, not tents) first appeared. During World War I (1914-1918) the Nissen hut was invented by a Canadian engineer. These were basically semicircular structures, made from pre-formed corrugated metal, with wood or masonry to close off the two ends.

The Quonset Hut of World War II, was based on the British metal Nissen huts of World War I. It was the U.S. Navy that asked for a new design in 1941, and a factory was built near Quonset Point, Rhode Island, to produce the new, American, design. Over 170,000 Quonset huts were built during World War II. Many were used by the military into the 1970s, and a few are still standing. Many were sold off as surplus after World War II, and can still be found in different parts of the country.

Quonset Huts are basically prefabricated structures made out of metal. With, or without, a concrete slab for a foundation, they can be quickly erected, and protect their inhabitants from the elements. Well some elements. But not the heat, or the cold. These structures were often not insulated, and being made of metal, they proved very hot in the tropics, and very cold in chilly climates. But they had plenty of screened windows, to let in what breeze was available. In cold weather, they usually had two or three space heaters, fueled by "jerry cans" of diesel. Unfortunately, one can only lasted about six hours, so someone either got up in the pre-dawn hours to put on some fresh fuel, or everyone woke up real chilly. And nothing woke you up faster than your bare feet hitting frigid concrete. The Quonset Huts rarely came with toilets, which, in typical army fashion, were in separate buildings, along with the showers. Again, in Winter, it was a bracing experience going to and from the shower.

The Quonset Hut had a semicircular roof, but also vertical walls, plus windows and doors. The original design was 36 feet long and 16 wide (with an eight foot ceiling). The most common design was 20 by 48 feet, with a ten foot ceiling. This model, the most widely produced, weighed about 3.5 tons, and required 325 cubic feet of shipping space to transport overseas. Some users, if they had the rank and resources, could add wood paneling, insulation and all manner of amenities to the interiors. The largest Quonset Hut was the three hundred, 40 by 100 foot, warehouse models, each of which weighed twenty tons, knocked down and ready for shipping.

After World War II, it took several decades for military prefab structure technology to make any more bold jumps. But by the end of the 20th century, new portable and prefab structures had appeared. Some of these were just better, "self-erecting" tents. Other used inflatable structures, or lightweight panels that quickly snapped together. Another popular portable structure was the 40 or 20 foot long shipping containers, that come loaded to a combat zone, but either leave empty, or stay and provide an instant building.