The Cupola: A Study of Form & Function


Sometimes, a seemingly small architectural detail can supply that extra layer of balance and character to set a building apart. Cupolas are an excellent example of a special touch that effectively impacts a building’s aesthetic appeal. But what exactly is a cupola? Does it provide both form and function? The answer is yes.

Cupolas are small, dome-like structures that sit on a building’s roof ridge and help define the structure’s centerline. Typically, the base is square, hexagon or octagon and is designed with windows or louvers (vents) on the sides. By bringing natural light and air into the spaces below, the cupola serves both decorative and practical purposes.

Historians believe cupolas date back to the 8th century and became prevalent throughout in New England in the 1800s. In rural areas, cupolas were a favorite ventilation technique for barns, allowing fresh air to circulate in and out through the rooftop while keeping the inside cool and dry. Some call them a “pre-air-conditioning” ventilation system.

Today, we add copulas to our residential architecture for rooftop interest and to introduce verticality to the building. It is a timeless way to add dimension and charm to our clients’ carriage houses, barns, guesthouses, and pool cabanas – while also providing ventilation, which is especially important in coastal regions.

We typically custom build our Cupolas with weather resistant Azek for the base, topped with copper or cedar shingles roofing material. (Alternately, Walpole Outdoors is a great resource.) The length of the building’s roofline dictates the size and scale of the cupola, so a cupola we design for a stately barn will be a different scale than one we design for a smaller pool house.

A standard rule of thumb is for every 25 feet of unbroken roofline there is 1 ¼” of cupola width.

Depending on the statement we wish to make, the cupola may be topped with a weathervane or lightning rod – or nothing at all. And, sometimes we will include a light in a windowed cupola, which, when lit at night, makes a beautiful evening impression.

Small but mighty, cupolas gracefully enhance a building’s exterior narrative by adding character and style. But they are not just a pretty face: by delivering natural light and ventilation, cupolas enhance a building’s interior space as well.