While the original cupola resembles a miniature dome, today's rooftop turrets appear in a wider variety of forms. Although round, dome-shaped cupolas still exist, structures with a polygonal shape with vertical walls and angular corners are prevalent in modern times. While square-shaped or rectangular-shaped cupolas dominate most building rooftops, other shapes do exist. An example is the Squire, an eight-sided cupola designed by Orson Squire Fowler during the middle of the nineteenth century. A phrenologist by trade, Fowler was also an amateur architect. Popularizing the octagonal house during his day, Fowler believed the eight-sided cupola served both an aesthetic and practical purpose. Today, cupolas are often an afterthought, a simple adornment to a rooftop for strictly ornamental purposes. Fowler's Squire, however, allows access to the inside of the structure. In this way, with windows donning each side of the simple structure, the cupola serves as a belvedere, allowing sunlight to shine through and an occupant to sit within and admire the scenery without. This design also helps to promote circulation in the building. Fowler believed these two things together helped to promote a healthier lifestyle.
Rooftop gazebos can be constructed with a widespread array of materials. Being predominantly hollow and made of stone, ancient cupolas were less weatherproof than they are today. Many modern-day cupolas are constructed of metal, a more durable and long-lasting material. Wood is another popular building material, as displayed by the Rustic, or Lodge, cupola. This style of cupola appears on barns, cabins, lodges, country homes and mountainside abodes. Cedar, redwood, poplar and white pine are types of wood used in the construction of cupolas. Sometimes lanterns are placed within a cupola, serving as a beacon in the darkness of the night. Other times a cupola serves as a belfry and a bell is built inside. However, Rustic cupolas typically do not have windows but are faced with louvers or an array of slanting, horizontal slats on each face of the structure. This design lets in light but forces out hot air. The louvers help promote air circulation within the building while ensuring privacy for those within.
Victorian cupolas are found most often on older houses, houses dating back to the Victorian age of architecture, which extended from 1837 to 1901 during the reign of Queen Victoria in Britain. Although the Victorian cupola can appear in a variety of forms depending on the type of Victorian architecture used, a few common traits define this particular structure. The pitch of a Victorian cupola's roof is often very steep and pointed and the faces curve as they taper upward. The roofs of these particular structures are often made of copper, a common feature during that era and beyond. Contrasting with the simplicity of the Rustic style, Victorian cupolas are ornate with brackets, shingles, moldings and wide, shaped windows, as opposed to simple, rectangular windows. The apex of the roof is usually topped with a metal pinnacle or weather vane.