Skylight / July 12, 2018 / Odo Vaillancour
The acrylic dome is typically mounted in an aluminum frame which is in turn mounted on a box called a "curb." Once the hole is cut in the roof to the manufacturers specifications the curb is typically constructed on-site to raise the skylight above the level of the roof sheathing. Site-built or factory-supplied flashings are used to seal the roofing around the curb. Domed skylights are available in clear smoked bronze or other tints. Some domed plastic skylights are flush mounted which means that the lens piece and flashing piece are both made of plastic and then placed on the roof without a curb. The problem with this type is that they are loud and very susceptible to leakage.
For one thing skylights are positioned in such a way that they are inaccessible unless they are operated by remote. Even in cases of motorized skylights which are easily manipulated there are still some disadvantages that are inherent to skylights that are not present or minimized in windows. Vertical windows lose less heat by convection when compared to skylights. Also since windows are generally protected by overhangs or shrubs they lose less heat by radiation. On the other hand skylights are directly exposed to the sky. Thus they lose more heat by radiation. Proper insulation can reduce this heat loss to a large extent. In the summer season skylights are more exposed to the direct heat of the sun than windows.
Before installing a skylight in your home you need to carefully evaluate what type of skylight will work best for you considering your specific requirements and how to install it in a way that it improves your homes energy efficiency. Its a sensible idea to evaluate the energy performance ratings of skylights based on the climate that you live in and the architectural design of your home. In the U.S. you can find labeled energy-efficient skylights which tell you the minimum energy performance rating criteria by climate. The physical dimensions of the skylight also greatly affect the lux level and temperature of the space it is being used for.