Auto body

A coachbuilder is a manufacturer of bodies for passenger-carrying vehicles.Coachwork is the body of an automobile or a bus or a horse-drawn passenger vehicle. The word coach was derived from the Hungarian town of Kocs. By extension coach also may be used for a railroad passenger car or railway carriage.

Custom or bespoke bodies require a separate chassis to avoid the vast expense of designing and building a suitable unibody or monocoque structure. While the enormous cost of suitable machinery to make steel structures may be avoided by moulding synthetic materials for one-off bodies the high costs of structural design and development remain prohibitively expensive.

As well as true custom or bespoke bodies coachbuilders also made short runs of more or less identical bodies to the order of dealers or the manufacturer of a chassis. The same body design might then be adjusted to suit different brands of chassis. For example Salmons & Sons' Tickford bodies with a patent device to raise or lower a convertible's roof, used on their 19th century carriages, or Wingham convertible bodies by Martin Walter

Custom body is the standard term in North American English. Coachbuilders are: carrossiers in French, carrozzeria in Italian, Karosseriebauer in German and carroceros in Spanish.

Coach-built implies that a body's frame is wooden but it may not be so. Coachbuilt also describes a recreational vehicle or motorhome which has been purpose-built. A whole new body has been made for a bare chassis as opposed to a conversion built inside an existing vehicle body.

A British trade association the Worshipful Company of Coachmakers and Coach Harness Makers, was incorporated in 1630. Some British coachmaking firms operating in the 20th century were established even earlier. Rippon was active in the time of Queen Elizabeth I, Barker founded in 1710 by an officer in Queen Anne's Guards, Brewster a relative newcomer (though oldest in the U.S.), formed in 1810.

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