Why Attic Ventilation Matters

How to Find the Right Attic Vents for Your Home

An attic gable with a circular vent

Proper attic ventilation is important, especially for homes located in climates where snow and ice dams are common. Take advantage of summer weather to inspect your home for adequate attic ventilation and make necessary repairs or improvements.

A well-ventilated attic helps expel warm air and refresh it with cooler outside air. The National Roofing Contractors Association (NRCA) says proper air circulation can help:

  • Remove excess heat and moisture from attics to prevent condensation that could lead to mold and mildew, structural damage and ice dams during winter.
  • Reduce the average air temperature inside an attic during summer.
  • Maintain the manufacturer's warranty on some asphalt shingle systems.

Types of attic vents: Attic ventilation recommendations range from 1 square foot of ventilation for every 150 square feet of attic space to 1 square foot for every 300 square feet. According to the NRCA, a common way to vent asphalt roofs is with non-powered or "passive" ventilation that balances air intake with air exhaust. Common passive vents include:

  • Ridge vents. Exhaust vents installed along the roof's peak that are either covered by shingles or exposed along the ridgeline.
  • Static vents. Individual protected exhaust vents installed near the roof's ridge.
  • Gable vents or wall louvers. Exhaust vents placed in walls at gabled ends of an attic that can function as both intake and exhaust vents.
  • Wind turbine vents. Exhaust vents that use wind power to turn an internal fan, drawing hot air from the attic. Compared to static vents, these can increase the rate at which air is expelled, depending on wind speed.
  • Soffit vents. Continuous or individual vents installed along an attic's soffits or eaves. Soffit vents should never be blocked by insulation.

The NRCA provides additional information about attic ventilation on its website.


State Farm® (including State Farm Mutual Automobile Insurance Company and its subsidiaries and affiliates) is not responsible for, and does not endorse or approve, either implicitly or explicitly, the content of any third party sites hyperlinked from this page. State Farm has no discretion to alter, update, or control the content on the hyperlinked, third party site. Access to third party sites is at the user's own risk, is being provided for informational purposes only and is not a solicitation to buy or sell any of the products which may be referenced on such third party sites.

The information in this article was obtained from various sources not associated with State Farm®. While we believe it to be reliable and accurate, we do not warrant the accuracy or reliability of the information. These suggestions are not a complete list of every loss control measure. The information is not intended to replace manuals or instructions provided by the manufacturer or the advice of a qualified professional. Nor is it intended to effect coverage under our policy. State Farm makes no guarantees of results from use of this information.