Mounting fans: Attic exhaust fans mount in the gable end or on the roof itself, just below the ridge or peak. Roof-mounted fans or ventilators are the most effective type. They require that the shingles be removed and a round hole be cut into the roof. In repairing the fan, the fan may have to be removed.

Roof pitch: The pitch of the roof will have an impact on the difficulty and labor involved.