Tips for assessing your needs.
Calculating attic ventalation.
But the shortcut is just as good and faster.
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.
To calculate nfa take the attic square footage 2 square inches of exhaust and square inches of intake nfa needed.
Hence you would need two square feet 600 300 of attic ventilation.
Enter square footage calculate or enter the square footage of the attic or area to be vented.
Typically building codes include minimum requirements applicable to attic ventilation.
Proper attic ventilation can be an impor tant performance consideration when design ing and installing steep slope roof systems.
The roofing industry also has practical guide lines for attic ventilation.
Width or area.
As an example in an attic that is 30 feet by 20 feet you would have 600 square feet of floor area.
Roof ventilation calculator enter your attic area or length and width to determine your ventilation needs.
Round your calculations up to the next highest number see ventilations requirements.
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.
Ridge vent intake vent calculator for standard gable attic.
Of vent space for every 150 sq.
According to the fha federal housing administration us for every 300 square feet of attic floor area you should have at minimum one square foot ventilation.
Most attic ventilation manufacturers list the longer formula on their websites and inside key product brochures.
Roof mount power fans are a type of motor driven attic exhaust vent that make up half of a balanced attic ventilation system for each roof.
Select ventilation product flex roll ridge vent multi roll multi purpose vent rigid roll ridge.
Ft you divide that by 150 to get 10 sq.
Here are the answers to the five most frequent questions pertaining to calculating attic ventilation.
To use this calculator first find the total square footage of the attic floor area.
Code requirements the international building code.
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.
The rule of thumb on the amount of vent space needed is approximately 1 sq.
So if your attic is 1 500 sq.
