Attic Info ...
Solar Powered Attic Fans - The How And Why Of Installing Them ... If there is inadequate ventilation in the attic and poor sealing between the attic and the other rooms in the house, attic fans powered by electric means can potentially draw air from the house into the attic... Not only does this compromise energy efficiency but it can also increase the risk of moisture problems in the attic... The highest fan speed will tend to coincide with the greatest heat from the sun and consequently the greatest need for attic ventilation...