Pole barn

Pole framing or post-frame construction (pole building framing, pole building, pole barn) is a simplified building technique adapted from the labor-intensive traditional timber framing technique. It uses large poles or posts buried in the ground or on a foundation to provide the vertical structural support, along with girts to provide horizontal support. The method was developed and matured during the 1930s as agricultural practices changed, including the shift toward engine-powered farm equipment and the demand for cheaper, larger barns and storage areas.

Pole building design was pioneered in the 1930s in the United States originally using utility poles for horse barns and agricultural buildings. The depressed value of agricultural products in the 1920s and 1930s and the emergence of large, corporate farming in the 1930s created a demand for larger, cheaper agricultural buildings. As the practice took hold, rather than using utility poles, materials such as pole barn nails were developed specifically for this type of construction, making the process more affordable and reliable. Today, almost any low-rise structure can be quickly built using the post-frame construction method.

Pole barn construction was a quick and economical method of adding outbuildings on a farm as agriculture shifted to equipment-dependent and capital-intensive agriculture—necessitating shelter for tractors, harvesters, wagons and the like in much greater quantities and sizes. Around North America, many pole-built structures are still readily seen in rural and industrial areas.

Poles, from which these buildings get their name, are natural shaped or round wooden timbers 4 to 12 inches (102 to 305 mm) in diameter. The structural frame of a pole building is made of tree trunks, utility poles, engineered lumber or chemically pressure treated squared timbers which may be buried in the ground or anchored to a concrete slab. Generally the posts are evenly spaced 8 to 12 feet (2.44 to 3.66 m) apart except to allow for doors. Buried posts have the benefit of providing lateral stability so no braces are needed. Buried posts may be driven into the ground or set in holes then filled with soil, crushed stone, or concrete.

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Wikipedia