The pole-building (also known as post-frame construction industry has grown steadily in North America, gaining more and more widespread application in the past 100 years.
Post-frame buildings are structurally efficient buildings composed primarily of: trusses, purlins, girts, bracing and sheathing. The primary element of the design incorporates square posts or wood columns, which are typically embedded in the ground or surface-mounted to a concrete or masonry foundation.
The post-frame building concept is not new. Many pre-historic peoples throughout the world used posts embedded in the ground to fashion sturdy structures for residences and other uses. For centuries, buildings along shorelines and in low-lying areas have been built on poles to elevate the structures above the guideline and/or water hazard. In rural areas, poles were used to erect sheds or temporary structures in 19th-century America. In all these cases, the limited life-span of poles in contact with the ground made them unsuitable for use longer than a few years, except in very dry areas or when rot-resistant strains of wood were used.
However, two significant technological developments in the twentieth century allowed the post-frame building to develop into a viable, long-lived structural system. First, pressure-treated materials that provided excellent durability, particularly poles that were initially developed for the electrical industry, became available for the construction of buildings. Secondly, large, lightweight metal sheeting was produced that could span supports spaced several feet apart. What remained was for builders to optimally use the advantageous features of these two materials in what is now known as the post-frame or laminated column building.
The availability of pressure-treated wood permitted the replacement of a continuous concrete foundation in conventional buildings with a vertical structural member that carried the live roof and dead building loads directly to the ground below the frost line.
The availability of lightweight, formed, metal roofing material permitted the use of spaced roof decking. The strength of the roofing materials resulted in a significant portion of the lateral building loads being transmitted to the end walls, to reduce the load on the supporting posts. The availability of trusses for a wide variety of spans further enhances and aides in the development of the post-frame building. Whereas trusses in conventional light-frame buildings are generally spaced 2-ft. or less on-center on stud walls, trusses became readily available that permitted truss spacing of anywhere from 4 to 12 ft. in post-frame construction. Each of these features contributed to the evolution of the modern post-frame building and its increasing popularity.
Pole barns have been built since the beginning of history; they are affordable and fast to make, and provide a good defense from the environment. But they were always looked upon as temporary buildings that couldn’t last. The Great Depression changed that. As materials were generally in short supply, people had to build with what was available.
H. Howard Doane is considered the major innovator in pole barns, as he created a number of ways to create pole barns. He started by finding ways to use 2×4 boards of any length to build pole barns by using making trusses. He patented his system, and then made it a point that his method was spread as much as possible. His Agricultural Service supervisor, Bernon G. Perkins, is credited with finding a way to change pole barns from temporary structures to permanent ones by using a different building method.
During World War II, the government imposed a limit of $1500 on new barns. This limitation was due to the lack of materials more than any other reason. Pole barns were perfect for this, as they are by nature very affordable to build, and only required a third of the materials of normal barns. Combined with innovations and new materials, pole barns were lifted to an entirely new level of popularity by the war. Afterwards, they stayed in fashion because of their utility and inexpensiveness, as well as how quickly they could be built.
Today’s structures that can take a lot more punishment than their predecessors from centuries past. With modern ways of treating wood, as well as creating materials that are affordable and sturdy, pole barns have gone from being extremely temporary structures to permanent structures. Their affordability and versatility is being matched today by some stunning architectural designs. Contact us today to discuss how a pole building could be right for your property.
(Excerpted from the National Frame Builder’s Association website: www.nfba.org.)