How Many Roof Vents Should I Have

Fan calculation as a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space.

How many roof vents should i have.

Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. Feet of attic space divided 50 50 between the inlets and outlets. Of vent space for every 150 sq. The venting works by air entering through the soffit vents then traveling up each rafter space to exit the roof through the ridge vent.

Attic ventilation requirements how many attic vents your roof needs industry standard for proper attic ventilation recommends for no vapor retarder type of attic insulation no paper plastic or aluminum layer between the attic floor and insulation layer 1 sq. Thus if your attic is 450 square feet you need roof vents equaling 3 square feet. The website also explains how much ventilation is needed. The rule of thumb on the amount of vent space needed is approximately 1 sq.

Intake vents located at the lowest part of the roof under the eaves allow cool. Near ridge of the roof. So if your attic is 1 500 sq. Keep in mind you should always consult with a professional roofing company when determining how many air vents your roof should have.

They should be divided equally between inlet and outlet vents and they can be used in any combination that will work with your roof s design. You ll need the square footage of your attic to calculate the number of roof vents that you should need. Ft you divide that by 150 to get 10 sq. The building requirements will probably tell you to place a certain number of soffit vents per square foot of ceiling space.

Some local building codes carry special considerations that take precedence. And this guideline you ll need a minimum of. Foot of ventilation for every 150 sq. For example if you have 1200 square feet of attic space you should need at least 4 air vents to ensure proper ventilation.

For example you might have to place one soffit vent and one other kind of vent for each 150 sq.