Venting Your Attic Space

Your actual living space is sealed and insulated at the attic floor the attic is outside this envelope.

Venting your attic space. This will help to avoid premature damage to the shingles or mold building up in moist hot. 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. 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.

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

Unless your roofing system has insulation on the roofing deck and is designed without ventilation your furnace should not be heating your attic. To determine the area multiply the length times the width in feet. So if your attic is 25 by 15 you ll need 2 5 feet of vent space. If your attic covers the entire house a measurement of its outside dimensions will give you the area of the attic space.

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. In the summer good attic ventilation reduces heat buildup. That cuts cooling costs and prolongs shingle life. 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.

Intake vents located at the lowest part of the roof under the eaves allow cool. In the winter warm moist air seeps into the attic from the living space below. 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. Here are four signs of an unventilated or under.

If there are asphalt shingles on your roof the attic must be ventilated to comply with the terms of the manufacturer s warranty. Whole house fans powered attic fans. An attic fan works by exchanging the hot air in your attic space for fresh air pulled through the vents. That keeps your attic dry and reduces ice dams.

Then divide the total area by 150 to find the total amount of vent space needed for your attic.