How Many Roof Vents

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.

How many roof vents.

1 square foot of ventilation for every 300 square feet of space. Always have a balanced ventilation system. If you want to learn more or are interested in a roofing job 1 800 hansons is at your service. Choose one of the following products to meet the recommended exhaust nfva of 528 square inches.

In no case should the amount of exhaust ventilation exceed the amount of intake ventilation. This means that you should add more roof vents than 1 per 150 square feet. Choosing round soffit vents for. Fan calculation as a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space.

Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation for every 300 square feet of attic floor space evenly split between intake and exhaust. You ll need the square footage of your attic to calculate the number of roof vents that you should need. Ventsure 4 foot strip heat moisture ridge vent with weather protector moisture barrier. Thus if your attic is 450 square feet you need roof vents equaling 3 square feet.

No vapor barrier and for some municipalities in hot climates. 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. For the number of soffit vents in the example divide 8 square feet of ventilation needed by 0 5 for the number of rectangular vents required 16 in the example. For example if you have 1200 square feet of attic space you should need at least 4 air vents to ensure proper ventilation.

But if your roof has a slope greater than 6 12 this means that there will be more volume in your attic than the actual square footage. For pitched roofs with vapor barriers. Use the calculator below to find out how many exhaust and intake vents you will need on your house. Ventsure 4 foot strip heat moisture ridge vent.