Originally designed for ventilation and to let in light, a cupola is a small round structure atop a building, often in the form of an open space surrounded by columns holding up the roof. Largely decorative nowadays, a cupola can also act as a sort of elevated gazebo, or may contain a light of some sort. Many home improvement websites offer free plans. Others require a free email membership or
. subscription to enable access to archives of cupola plans. Depending on the size and stylistic designs, some versions available online are well thought out, however it's important to make sure free plans have been designed by someone with enough experience to prevent a dangerous accident or collapse. Particularly for adding a cupola to an existing building, it's paramount to understand roof design, because incorrectly attaching something to the structure of a roof can cause costly damage. As with any building structure, it may be best to consult a professional prior to beginning a project, especially in absence of experience. For more information, please see: http://www.reference.com/browse/cupola
