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.

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. Ft you would need at least 5 2 sq. Of vent area with half under the eaves in the soffit and half near the peak as either gable or ridge vents. The house measures 30 feet by 50 feet.

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. Calculating ventilation area of attic kitchen ventilation text. 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. The majority of the requirements related to attic ventilation have not changed much from the previous editions.

Soffit vents alone are not enough to provide proper attic ventilation. Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca. The federal housing administration recommends 1 square foot of attic ventilation for every 150 square feet of attic space. Here are the answers to the five most frequent questions pertaining to calculating attic ventilation.

Daily activities in your home such as showering dishwater laundry or having the furnace on generate heat and moisture in the air. Divide the attic s square footage by 150. Ventilation can be accomplished using various products and techniques. Cool air in hot air out.

Calculate or enter the square footage of the attic or area to be vented. Let s use the following simple ranch house for an example. The ventilation amount and opening size requirements can be found in section 806 roof ventilation of chapter 8 roof ceiling construction. The following are the requirements taken directly from the irc.

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. But the shortcut is just as good and faster. Most attic ventilation manufacturers list the longer formula on their websites and inside key product brochures. Calculation q a.

Proper air ventilation in the roof prevents costly problems like.