The Importance of Proper Attic Ventilation

Proper Attic Venting

• A properly ventilated attic should have about 1 square foot of ventilation for every 300 square feet of ceiling. At least 50 percent of the outgoing air must be through soffits or gable vents, and 50 percent of outgoing air must be through roof or ridge vents. If you're using screens on your vents to prevent birds or bugs, the amount of venting needed is doubled because the screens can lower the efficiency of the vents. You can determine the effectiveness of your attic ventilation by entering your attic on a cool day. If the temperature is high, the air is not being properly vented and you may not have enough soffit vents to properly vent the hot air.

Energy Consumption

• Proper attic ventilation is important to the overall energy efficiency of your home because it helps to reduce energy consumption by heaters and air conditioners. In a poorly-vented attic, temperatures climb in the summer and drop in the winter so the heating and air conditioning units must work harder to maintain the desired temperature. With proper ventilation these and other appliances don't have to work as hard to maintain temperatures in the interior of your home.

Roof Quality

• Attics that heat to extreme temperatures can lead to your shingled roof deteriorating more rapidly, so properly venting your attic helps to ensure the life of your roof. Many shingle manufacturers require a properly vented attic as a condition on the shingles' warranty. If the shingles are damaged and the attic isn't properly vented, the manufacturer may deem the warranty void.

Moisture

• In regions where the climate is cold in the winter, proper attic ventilation prevents moisture from forming on your insulation, joists and other structural material, shingles and your roof. When an attic isn't vented properly, the moisture in the air condenses, making these things damp. Dampness can lead to mold and mildew growth and minimizes the durability and function of your attic and structural components. Moisture can also freeze on roof edges, which leads to ice dams forming. With a properly vented attic, the chances of these dams, which can also damage your roof and may result in leaks, is reduced.