Octagon architecture

Octagon houses were a unique house style briefly popular in the 1850s in the United States and Canada. They are characterised by an octagonal (eight-sided) plan, and often feature a flat roof and a veranda all round. Their unusual shape and appearance, quite different from the ornate pitched-roof houses typical of the period, can generally be traced to the influence of one man, amateur architect and lifestyle pundit Orson Squire Fowler. Although there are other octagonal houses worldwide, the term octagon house usually refers specifically to octagonal houses built in North America during this period, and up to the early 1900s.

Early examples, before Fowler:

Both houses are large brick buildings in the classical tradition. They may be seen as precursors, but are somewhat different from the Victorian octagon houses which are essentially domestic structures.

The leading proponent of octagonal houses was Orson Squire Fowler. Fowler was America's foremost lecturer and writer on phrenology, the pseudoscience of defining an individual's characteristics by the contours of the head. In the middle of the 19th century, Fowler made his mark on American architecture when he touted the advantages of octagonal homes over rectangular and square structures in his widely publicized book, The Octagon House: A Home For All, or A New, Cheap, Convenient, and Superior Mode of Building, printed in the year 1848. As a result of this popular and influential publication, a few thousand octagonal houses were erected in the United States, mostly in the Midwest, the East Coast and in nearby parts of Canada.

According to Fowler, an octagon house was cheaper to build, allowed for additional living space, received more natural light, was easier to heat, and remained cooler in the summer. These benefits all derive from the geometry of an octagon: the shape encloses space efficiently, minimizing external surface area and consequently heat loss and gain, building costs etc. A circle is the most efficient shape, but difficult to build and awkward to furnish, so an octagon is a sensible approximation. Victorian builders were used to building 135° corners, as in the typical bay window, and could easily adapt to an octagonal plan.

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