Attic fans are installed either on a gable vent or through the roof. Their purpose is to ventilate and exhaust the air inside the attic directly outside. Even if the temperature outside is hot, this air movement can help immensely to cool the attic. Attic ventilation is crucial to homeowners because attics can act like an oven on top of your home, constantly reheating the living space. When mid-summer comes around a typical attic can reach temperatures of over 140 degrees! In a two-story home, this heat can make the top floor unbearable! For this reason, an attic fan alone can help homeowners feel more comfortable at home.