Proper Venting for a Roof

Gable Vents

• Gable vents are the vents that you see installed on the side wall of the house, inside the gable. The gable is the triangular-shaped section of the wall that lies underneath the roof of the house. A passive gable vent functions best when it is used with soffit vents and ridge vents. If you don't have soffit or ridge vents, or you want to improve the ventilation provided by the gable vent, you can install a fan inside the attic that expels air out through the gable vent. A fan such as this is controlled by a thermostat, which turns the fan on and off when the temperature in the attic reaches a certain point. The gable vents also serve a decorative function, as they are plainly visible on the side of the house.

Roof Vents

• Roof vents sit on the roof's exterior, usually a few feet away from the roof peak. There are several different styles of roof vents. Passive vents have no moving parts and just allow the hot air inside the attic to rise through them naturally. Turbine vents are dome-shaped vents with slits cut into the sides that are used to catch the wind as it blows, which rotates the vent and draws air out of the attic. Solar-powered roof vents contain fan blades inside the vent housing that are powered by the sun.

Soffit Vents

• A soffit vent plays an important role in protecting your roof. This is a vent that is located underneath the eaves of your house and draws fresh air in from outside. This air flows up along the inside of the roof before being vented out of the attic, usually through ridge vents. Drawing cooler air into the attic during the summer helps protect the shingles by cooling the attic. In the winter, the soffit vents draw cold air into the attic, which prevents the rooftop snow from melting too fast. When snow melts rapidly, it can freeze too quickly, causing ice dams, which damage the roof.

Ridge Vents

• A ridge vent is a vent installed along the top edge of a roof. When a new roof is installed, there is a gap between the edges of the sheathing along the peak. The ridge vent is installed in this gap, and it is covered with ridge cap shingles. The ridge vent allows the warm air that rises to the surface to flow out of the attic, a process that is enhanced by the wind. The wind creates an area of low pressure around the ridge vent, providing less resistance for the high-pressure air found inside the attic.