to store large quantities of hay or other materials in areas easily accessible by vehicles, machines, and people. In the United Kingdom a pole barn refers to a type of Dutch barn. Design The design of most pole barns is simple. Poles make up the outer walls and support the roof system, usually pre-engineered wood trusses with a roof sheathing. Poles are usually spaced 8' apart, with the trusses bearing directly on the poles. Some variations in design call for truss carrying beams between the posts with trusses sitting on them. The exterior walls consist of girts attached horizontally to the post with the exterior sheathing attached to them. Exterior walls may be finished with corrugated metal, plywood sheathing, vinyl siding, or other cladding. Roof materials are generally corrugated metal but may be finished using any typical roofing product. Depending on the function of the barn, there can be slight differences in style. For instance, a barn used for storing hay may lack any kind of lower exterior wall, whereas a pole barn used to house livestock would have some form of wall meeting the roof. History of Pole Barns In the 1930s, post-frame construction had its start with the development of two key components: availability in rural areas of wood telephone and electricity poles, and corrugated steel sheeting. By using poles embedded in the ground, along with steel roofing and siding, the amount of framing, siding, and foundation material needed to construct a barn was drastically reduced. The columns were literally telephone poles – hence the term 'pole barn'. After World War 2, 'poles' were replaced by solid sawn posts, usually 4×6 or 6×6. The posts were chemically treated to resist decay, greatly increasing the useful life of a building. In the 1950s and 1960s, metal-plate-connected wood trusses were developed, increasing roof spans, eventually up to 100′ (30 m). In the 1970s and 1980s, solid sawn posts were supplemented by laminated 2×6 and 2×8 posts, allowing taller buildings. Since the 1980s, pole barns have been adapted for a variety of uses, including residential garages, retail stores, light commercial buildings, and professional offices. Corrugated metal is still very common, but other exteriors such as vinyl siding, stucco, and cement board are also used. The National Frame Builders Association is a trade group for the post-frame construction industry. Rice barns Rice barns are used ubiquitously in the rice cultivating world for