Benefits of rooftop ventilation fans include reducing the temperature of the upper floor, lengthening the life of the roof and the potential to save homeowners up to 30 percent on air conditioning costs. Additionally, if adding a humidistat to the attic fan, there is a reduction of moisture in the attic, which keeps the attic dry in the winter.
Attic and roof ventilation with a fan is important to keep the moisture and temperature level as the weather changes. When it becomes cold outside, air leaks occur around attic light fixtures, access panels and fans, which brings moisture into the attic space. This moisture may cause mold growth and weaken the roof.
There are several options available for homeowners who want to install a rooftop ventilation fan, including nonmechanical fans, solar fans and electric fans. There are also whole-home ventilation systems available. Many older homes have nonmechanical fans or gable vents, which appear on the side of the roof. These vents help keep the attic cooler but often create hot spots. A more powerful fan eliminates this.
Solar and electric fans create a steady flow of air into the attic without using passive venting. However, this also helps create more moisture, especially when in areas of high humidity, so experts recommend adding a dehumidifier system if installing a new roof fan.