Because the roofs face the sun, they accumulate considerable heat in the warm season. Attic ventilation provides an outlet for this heat gain and allows fresh air to enter the attic. Attic ventilation also prevents moisture buildup in the cold season. Cooler air cannot carry both moisture and warm air.
Proper attic ventilation helps address excess heat and moisture that could otherwise wreak havoc on your home. The buildup of heat and moisture in an attic causes predictable but different problems in hot and cold climates; areas with hot summers and cold winters can suffer the effects of both. Insert the entrance grilles above the eaves, also known as ceiling grilles. Ceiling vents allow outside air to enter the attic.
They work in correlation with ceiling grilles for proper airflow. Roof vents are important because they extend the life of the roof, reduce energy costs, and reduce extreme indoor temperatures. They also prevent damage to shingles and prevent them from cracking. Attic ventilation fans help cool attic air by blowing suffocating hot air inside the attic and bringing in cool air from outside.
This prevents warm air from leaking into your home and raising the temperature in the living space, reducing the load on the air conditioner. As you turn up the heat and complain about the cold, all that warm humid air in your attic is impacted by the cold air in your attic. Poor insulation is usually the culprit, although if you enter the attic on a sunny winter day, the sun can heat the attic space more than your oven. The goal is to have an even flow of cold air from the outside through the attic and out through the exhaust, carrying with it the warm and humid air from the attic.
It may start to seem like attic fans aren't worth it and could cause more problems than they solve. I have a large attic with air vents and vents on both ends of the attic to keep the air flowing. I was told that the 2 attic vents are the only attic vent I have (the house has ventilated panels, all the other soffit covers are ventilated). In these climates, warm attic spaces are eliminated by installing a thermal barrier along the roof line, rather than the attic floor.
Unlike static models, which rely on passive ventilation, electric exhaust grilles, such as this solar powered ventilation from EcoHouse, have an electric or solar fan that draws air from the attic. Another disadvantage is that homes that do not have air-sealed attics may lose some amount of their air conditioner from the suction of the attic ventilation fan, depending on how much ceiling ventilation space is available.