The Cool Attic 24 in direct drive two-speed whole house fan is designed for houses with 1200 to 1800 sq-ft. attics. It offers an efficient way to reduce cooling costs by pulling fresh air in from the outside, expelling the warm air up into the attic and pushing it out through the attic exhaust vents. This unit requires a minimum of 8 to 10 sq-ft of net free exhaust vent area to perform correctly. Low vibration direct drive design and a four-blade galvanized steel fan assembly contribute to quiet and reliable performance.