Building Science Attic Fans

However since the 2009 edition of the irc attics can be designed to be either vented or unvented.

Building science attic fans.

Ventilation fans ventilation fans or powered attic ventilators are designed to cool the attic pushing out the hot attic air and rushing in a flow of cool outside air. Using a fan to blow hot air out of the attic doesn t address the radiant heat flow from the roof to the attic floor. A building science consulting and full service architecture firm specializing in building technology for all types of buildings including commercial institutional and residential. If the military decides they also want the project to achieve leed or other sustainability certifications those would also need to be checked to determine the most stringent requirements.

Attic ventilation is the britney spears of building science no discussion would be complete without it but it contains absolutely no substance. Upcoming events renovation and rehabilitation. Much of that heat then conducts downward and finds its way into the house. Using a fan to blow hot air out of the attic doesn t address the radiant heat flow from the roof to the attic floor.

The science behind attic ventilation however is sound. Much of that heat then conducts downward and finds its way into the house. Bill rose author of moisture in buildings founder s note. It really is a design choice.

Throughout the balance of this digest the terms attic and roof will and can be used interchangeably. These fans circulate the air within the attic pulling fresh. At least 1 sq. Building codes vary though so do check with your local building.

Of vent for every 300 sq. Attic fans serve a different function removing the hot and moist air from the attic and leaving the space below the attic floor alone. The icc also has the international wildland urban interface code 505 10 which limits the amount of attic ventilation openings in regions of elevated fire danger. Ventilating attic spaces is often viewed as a technical requirement for steep slope roof assemblies as well as a building code requirement.