Cupolas

Cupolas, small roofed structures placed on top of many older buildings, have been a common sight on American residential buildings for centuries. A cupola is essentially small extension of the main roof placed at the roofline of many barns, stables, garages, gazebos and colonial-style homes. Usually topped with a weather vane, it is not unlike a very short steeple, and can add a rustic touch to any design.

Tradition and Function

The origins of the modern-day cupola come from two distinct periods in history. Coming from the Latin for "small cup" or "small dome," the word "cupola" originally referred to the central dome of many Italian Renaissance cathedrals. These domes were placed in the center of the roof and usually had large, high windows to light the interior. At the highest point, there was often an open hole covered by a much smaller roofed structure known as a "lantern." This lantern served both to allow more light into the cathedral and to aid in air circulation.

The modern day cupola is a direct, smaller descendant of this Renaissance tradition. An innovation of the Victorian era, these cupolas serve the same function as the lanterns of Florence's cathedrals. Placed over a hole in the center of a barn, stable or large room in a Victorian home, a cupola allows letting light enter. In barns and stables, this helps keep hay in the upper lofts dry by continuously circulating hot air as it rises.

Style and Form

In general, most modern cupolas are ornamental. These structures are added to homes, garages and outbuildings to give a traditional flair and break up the monotony of a flat roofline. Cupolas are normally of wooden construction with either a shingle or metal roof. The sides are open, usually covered with windows or wooden slats called "louvers" to admit light or allow air circulation in cases where it actually covers a hole in the roof.

A good rule of thumb when choosing the size of a cupola is to measure the section of roofline where it will be installed, then make the base of the structure one inch wide for every foot of roofline, rounding up if necessary. For instance, a garage with a 23.5-foot roofline would need cupola with at least a 24-inch base. This proportion keeps the cupola from appearing too small and out of place from the ground.

Weathervanes and Cupolas

Another hold over from the rustic history of American-style cupolas is the weather vane. Placed on top of barns, stables, homes and public buildings since colonial times, a weather vane accentuates the vertical line created by a cupola. These pieces, usually made of copper or brass, are installed to add an even more personalized touch to many homes, particularly in rural areas. In addition to its ornamental value, a weathervane often doubles as a lightning rod, protecting homes built in parts of the country where storm damage is common.