Venting Your Attic Space

Unless your roofing system has insulation on the roofing deck and is designed without ventilation your furnace should not be heating your attic.

Venting your attic space.

If your attic covers the entire house a measurement of its outside dimensions will give you the area of the attic space. In the summer good attic ventilation reduces heat buildup. 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. That cuts cooling costs and prolongs shingle life.

To choose the proper ventilation system for your attic you ll first need to know the total area of your attic. Your actual living space is sealed and insulated at the attic floor the attic is outside this envelope. An attic fan works by exchanging the hot air in your attic space for fresh air pulled through the vents. This is easy to accomplish in simply.

That keeps your attic dry and reduces ice dams. If there are asphalt shingles on your roof the attic must be ventilated to comply with the terms of the manufacturer s warranty. Intake vents located at the lowest part of the roof under the eaves allow cool. Don t avoid ventilating your attic for fear you re letting cold air into the house.

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. 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. Good ventilation allows the heat and moisture to escape. Whole house fans powered attic fans.

In the winter warm moist air seeps into the attic from the living space below. So if your attic is 25 by 15 you ll need 2 5 feet of vent space. This will help to avoid premature damage to the shingles or mold building up in moist hot. To determine the area multiply the length times the width in feet.

Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Vent the roof deck. 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. The net free vent nfa area of each vent you have installed should be.

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.