Formula For Proper Attic Ventilation

Ok to determine how much ventilation area you need for your house all you need to know is the square foot area of the attic to be ventilated.

Formula for proper attic ventilation.

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. The majority of the requirements related to attic ventilation have not changed much from the previous editions. Calculating ventilation area of attic kitchen ventilation text. Ventilation can be accomplished using various products and techniques.

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. Let s use the following simple ranch house for an example. Here are the answers to the five most frequent questions pertaining to calculating attic ventilation. The federal housing administration recommends 1 square foot of attic ventilation for every 150 square feet of attic space.

Daily activities in your home such as showering dishwater laundry or having the furnace on generate heat and moisture in the air. Cool air in hot air out. Calculation q a. Divide the attic s square footage by 150.

For a 30 x26 attic 780 sq. Proper air ventilation in the roof prevents costly problems like. Most attic ventilation manufacturers list the longer formula on their websites and inside key product brochures. Soffit vents alone are not enough to provide proper attic ventilation.

The following are the requirements taken directly from the irc. The house measures 30 feet by 50 feet. Attic mold rotting of roof sheathing and framing shortened roof life cracked paint and siding failure or an overheated home. But the shortcut is just as good and faster.

Before we explore how to ventilate an attic space it is prudent to understand how much ventilation is needed. Ft you would need at least 5 2 sq. Let owens corning roofing help you calculate exactly how much ventilation you will need for a healthy and balanced attic with our 4 step ventilation calculator. Calculate or enter the square footage of the attic or area to be vented.

Of vent area with half under the eaves in the soffit and half near the peak as either gable or ridge vents.