Enter square footage calculate or enter the square footage of the attic or area to be vented.
Figuring 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.
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.
Length x width of attic in feet 150 total sq.
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Intake vents located at the lowest part of the roof under the eaves allow cool.
We have calculators for intake and exhaust roof venting.
Of total vent space needed.
A 50 x 30 attic would have a total area of 1 500 sq.
Let s use the following simple ranch house for an example.
Enter the length and width of the attic floor or the total square footage of the attic floor.
As an example in an attic that is 30 feet by 20 feet you would have 600 square feet of floor area.
The house measures 30 feet by 50 feet.
The first step is to check out this 60 second video and learn about the 300 1 rule the difference between intake and exhaust ventilation and why proper ventilation is so important to get right to help calculate your attic ventilation needs visit gaf ventilation calculator.
Multiply the length of the attic times the width in feet to find the attic area then divide by 150 to find the total square feet of vent space needed.
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.
Figure 1 soffit to ridge attic ventilation.
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.
Calculating ventilation area of attic kitchen ventilation text.
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.
Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.
Roof attic ventilation calculator calculate how much ventilation you need for your roof.
Ft divided by 150 equals 10 sq.
Other options to meet your attic ventilation needs are.
How do you pick the right attic vent.
Standard attic vents like af 50 s ventilation fans or solar powered attic fans.
Always consult a design professional for cathedral ceilings insulated roof decks etc.
