When selecting a skylight, size is an important factor because if the skylight it too large then it will bring in too much light and heat. Often, the rule is that a skylight will be able to brighten a room twenty times its size. Placing a skylight where there is a lot of sun-exposure can lead to the area getting overheated, especially in warmer climates. Typically, a northern or eastern exposure position is recommended.
Skylights are available in a variety of shapes and sizes. The most common shapes include rectangular, circular, oval, diamond, triangular, multi-sided, and tubular.
Skylights often have one of three functions: allowing natural light in, ventilation, or moisture control.Light-emitting or day lighting skylights use traditional fixed designs, which capture the light and reduce overheating and heat loss. Ventilation
Ventilating a building with an operable skylight releases the hot air that naturally accumulates near the ceiling. Ventilating skylights usually open outward at the bottom, and some units vent through a small, hinged panel. Installation
Even the most energy-efficient skylight must be properly installed to ensure that it achieve its energy performance. In addition to following the manufacturer's guidelines, it's also important to consider slope and moisture control during installation.