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. The house measures 30 feet by 50 feet. Ft you would need at least 5 2 sq. The federal housing administration recommends 1 square foot of attic ventilation for every 150 square feet of attic space. 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.

Of vent area with half under the eaves in the soffit and half near the peak as either gable or ridge vents. Ventilation can be accomplished using various products and techniques. Proper air ventilation in the roof prevents costly problems like. Calculation q a.

But the shortcut is just as good and faster. Cool air in hot air out. Before we explore how to ventilate an attic space it is prudent to understand how much ventilation is needed. 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.

Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca. For a 30 x26 attic 780 sq. Ensuring your home has the proper attic ventilation according to these guidelines however can save yourself the stress and hassle of an emergency roof repair. 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.

Let s use the following simple ranch house for an example. The following are the requirements taken directly from the irc. Attic mold rotting of roof sheathing and framing shortened roof life cracked paint and siding failure or an overheated home. Most attic ventilation manufacturers list the longer formula on their websites and inside key product brochures.

Calculating ventilation area of attic kitchen ventilation text. Calculate or enter the square footage of the attic or area to be vented. Divide the attic s square footage by 150. Here are the answers to the five most frequent questions pertaining to calculating attic ventilation.

Soffit vents alone are not enough to provide proper attic ventilation.