When choosing a skylight, one option you want to consider is whether or not your skylight will be operable. Operable skylights can be opened to vent heat buildup and let in fresh air.
Some models can be operated via manual hand cranks, while more-sophisticated, electronic models can be operated by a wall switch or remote control. The highest-end models operate automatically via temperature sensors and rain-triggered closing mechanisms. Some manufacturers, such as Velux America, offer operable skylights for deck-mounted installation, as well as self-flashing and curb-mounted models.
Manual skylight controls
Basic manual-operating skylight models are an economical option for providing fresh air and natural light. They are operated via an extending rod (shown above) and are designed to be used in ceilings less than 15 feet high. For within-reach applications, a simple hand-crank (shown top left) is often preferred.
Electronic skylight controls
In recent years, electronically operated skylight controls have become an increasingly popular choice for virtually hands-free operation. A simple two-function model can be wired directly to a wall-mounted light switch. More complex models, including types with built-in shades and other features, can be controlled by a special wall console or even wireless remote control. Some remote controls, such as the one shown below, can be programmed to open or close the skylight at a preset time. 
Automatic operating skylights
With some higher-end skylight models, integrated heat sensors trigger the skylight to open when the interior heat reaches a preset temperature, and exterior rain sensors automatically close the unit when moisture poses a threat to the interior space.
