Length x width of attic in feet 150 total sq.
Calculating attic ventilation needs.
Other options to meet your attic ventilation needs are.
Divide the square footage item 1 by 300.
Divide the attic s square footage by 150.
The federal housing administration recommends 1 square foot of attic ventilation for every 150 square feet of attic space.
Calculate the square footage of the attic space.
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.
Of total vent space needed.
Most attic ventilation manufacturers list the longer formula on their websites and inside key product brochures.
Calculating ventilation area of attic kitchen ventilation text.
Let s use the following simple ranch house for an example.
If you are in the puget sound area of washington state and would like to have a free attic ventilation evaluation or roof estimate please contact us at 253 445 8950 or fill out our quick estimate form.
For balanced ventilation an equal amount of intake vent area net free area should also be installed.
Use avp s roof vent calculator to determine the number and size of exhaust vents you will need.
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.
The house measures 30 feet by 50 feet.
Standard attic vents like af 50 s ventilation fans or solar powered attic fans.
Hence you would need two square feet 600 300 of attic ventilation.
The two square feet is divided equally between the intake and the exhaust one square foot for each.
Calculation q a.
But the shortcut is just as good and faster.
Use our easy 3 step attic ventilation calculator to determine your attic square footage and ventilation needs.
Tips for assessing your needs.
A 50 x 30 attic would have a total area of 1 500 sq.
Calculate the total vent area needed.
Calculating attic ventilation requirements.
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.
Ft divided by 150 equals 10 sq.
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.
Result of item 1 300.