Attic Air Circulation

In the summer natural air flow in a well vented attic moves super heated air out of the attic protecting roof shingles and removing moisture.

Attic air circulation.

Soffit vents may leave air trapped at the top of your attic. Baffles are available at home centers. In hot humid climates ventilation will not keep an attic cool although air circulation combined with an attic fan can help reduce cooling costs. Solar attic fans do just that.

Attic ventilation works best in mild to cold climates. Whole house fans powered attic fans. Proper air circulation in the attic is all about preventing moisture buildup. Static roof line vents are effective for ventilation but generally aren t recommended due to issues with leaks.

If the attic is insulated with fiberglass batts just pull back any that are blocking the flow of air. The solution is to add baffles which allow air to flow past the insulation photo 9. The ice traps water behind it allowing the water to seep back under the shingles and leak through the roof. Fans and vents may be installed on the roof system that will draw the air out of the attic space and exhaust it to the exterior.

These ice dams form when warm attic air melts the snow on the roof and the water refreezes along the colder edge of the roof. During the summer soffit and gable vents draw cooler air from outside the house to replace hot air that collects in. These fans may be controlled by a switch or a thermostat which detects heat build up in the attic space and automatically exhausts the attic space. Gable vents may circulate air through only a small percentage of your attic.

The insulation will resist heat transfer into the house. Most solar attic fans are surface mounted meaning that they are installed directly through the roof surface where they are most efficient. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Increased ventilation will make the entire roof cold and reduce or eliminate ice dams.

That means air can t flow from the soffit vents to the roof vents. Intake vents located at the lowest part of the roof under the eaves allow cool. That said venting an attic is not always a complete energy efficient solution. If your attic is well insulated the insulation might be plugging the spaces between rafters just above exterior walls.