Attic Fans That Make a Difference You Can Feel

Attic Ventilation Strategy

• Because the importance of ventilating attics has been well understood for some time, homes are always built with soffit vents to draw stagnant air out of the attic and fresh air into it. Additionally, many homes use ridge vents, gable vents, rafter vents and other ventilation components to assist in attic air circulation. Installing and maintaining attic insulation is also a vital component of a good attic ventilation strategy. Insulation prevents damp air from rising up into the attic from below.

Fans

• For those homes where ventilation and insulation alone don't eliminate moisture, installing attic fans is another useful strategy for improving air circulation in the attic. Fans cool a hot attic in the summer by drawing in cooler fresh air from the outside and removing hot air outside. During winter, fans help prevent ice damming on the roof by drawing cool air into the attic, mitigating the temperature difference that causes damaging ice dams to form on your roof in the first place.

Powered Attic Fans

• Avoid the use of powered attic fans; you will surely feel the effects of a powered attic fan but not in the way you want. Powered attic fans tend to pull air-conditioned air up from the home below the attic, particularly if the attic is not well-sealed. This decreases air circulation in the attic. Worse, it makes your air conditioner work harder to keep the space below at a comfortable temperature, reducing the air conditioner's energy efficiency and boosting your energy bill. When combined with the electricity costs required to continuously run powered attic fans, this option is almost never cost-effective.

Improving Fan Performance

• To get the most performance out of your unpowered attic fans, check your attic insulation at least once a year to see if it's soggy or waterlogged and replace any insulation that is. The air circulation that fans deliver depends on a tightly sealed attic. Installing rafter vents and keeping soffit vents clear of debris and obstruction also improve the performance of your unpowered attic fans by making sure soffit vents are able to pull fresh air into the attic.