Air-supported structure

An air-supported structure is a building whose shape and strength come entirely from internal air pressure inflating a pliable fabric envelope, with entry controlled through airlocks rather than ordinary doors. The air inside is kept at a pressure typically less than one percent above the surrounding atmosphere, just enough to counter wind and other outside loads, and a pressurization system continually makes up for any leakage since the envelope need not be perfectly sealed. Most air-supported structures take a dome shape because it encloses the most volume for the least material, and the type is used for sports and recreation halls, warehouses, temporary shelters and radar domes, in forms ranging from temporary installations to permanent structures built to standard building codes.