Venting Your Attic Space

Whole house fans powered attic fans.

Venting your attic space.

That cuts cooling costs and prolongs shingle life. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. If your attic covers the entire house a measurement of its outside dimensions will give you the area of the attic space. If there are asphalt shingles on your roof the attic must be ventilated to comply with the terms of the manufacturer s warranty.

In the winter warm moist air seeps into the attic from the living space below. An attic fan works by exchanging the hot air in your attic space for fresh air pulled through the vents. Here are four signs of an unventilated or under. That keeps your attic dry and reduces ice dams.

If the attic space is going to be conditioned either for living or mechanical purposes or if a home design calls for a vaulted ceiling provision r806 3 in the international residential code calls for the roof deck above the space to be vented continuously from the eave to the ridge. This will help to avoid premature damage to the shingles or mold building up in moist hot. Then divide the total area by 150 to find the total amount of vent space needed for your attic. The net free vent nfa area of each vent you have installed should be.

Intake vents located at the lowest part of the roof under the eaves allow cool. Good ventilation allows the heat and moisture to escape. To choose the proper ventilation system for your attic you ll first need to know the total area of your attic. Poor insulation is usually the culprit although if you enter the attic on sunny winter day your attic space can be warmed by the sun more than your furnace.

To determine the area multiply the length times the width in feet. Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space. In the summer good attic ventilation reduces heat buildup. Your actual living space is sealed and insulated at the attic floor the attic is outside this envelope.

Don t avoid ventilating your attic for fear you re letting cold air into the house. 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. Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge. Vent the roof deck.

This is easy to accomplish in simply.