Attic ventilation serves several purposes during all four seasons of the year, among them being added comfort, protection against damage to materials and structure, and reduced energy consumption. But the most important function is to provide a uniform flow of cool air along the underside of the roof sheathing which in turn carries the heat out of the attic. Proper ventilation is also required in order to validate the manufacturer's warranty for your roofing system.

During warm weather, ventilation is necessary to divert radiant heat from the sun. Without ventilation that heat conducts through the roof sheathing, through the attic, and into the living areas. This is not only uncomfortable, but raises cooling costs. Eventually the accumulation of heat begins to have costly consequences on your roofing system as well. The shingles begin to prematurely fail due to the distortion and deterioration caused by the excess heat. This can lead to further problems, such as structural and interior repairs needed to correct the effects of water infiltration.

In the cold weather months the temperature conditions are reversed. Heated indoor air travels from the home and into the attic, carrying moisture along with it. When moist air hits cooler rafters, trusses, and roof sheathing it condenses as water droplets or frost. Eventually this condensation drips onto the insulation below, reducing its effectiveness. Moisture buildup has long-term effects also, such as wood rot and deterioration of the roofing materials. In areas where snowfall is common, ice dams can form, which have even more devastating effects on your home. Please see FAQ - What are ice dams and how do they affect roofing systems?

An effective ventilation system is necessary to provide the steady, high volume of air movement needed to prevent the problems mentioned above. That means the system components must be sized and positioned to provide a constant flow of air, moving in a constant direction. The thermal effect creates a natural circulation of air because as warm air rises, cooler air falls. A well designed system assists this momentum by placing intake vents at the lowest point of the attic and exhaust vents at the highest. There are a wide range of intake and exhaust components to choose from allowing us to tailor ventilation systems to the specific characteristics of every home. Ventilation devices include ridge vents, turbine vents, power fans, and static or fixed vents. Please see Goods & Services - Attic Ventilation.