How Many Vents Does My Roof Need

Near ridge of the roof.

How many vents does my roof need.

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. The net free area nfa rating indicates the amount of space each roof vent covers. For example if you have 1200 square feet of attic space you should need at least 4 air vents to ensure proper ventilation.

You will need to have 1 square foot of vent area for every 150 square feet of attic space. Choosing round soffit vents for. Keep in mind you should always consult with a professional roofing company when determining how many air vents your roof should have. For example you might have to place one soffit vent and one other kind of vent for each 150 sq.

This helps make it easy to calculate how many vents you need for your attic once you ve determined your requirements. As a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space. In no case should the amount of exhaust ventilation exceed the amount of intake ventilation. 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.

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. If your attic floor has a vapor barrier you will need one square foot of nfa per every 300 square feet of attic floor area half of that will be intake half for exhaust. Always have a balanced ventilation system. 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.

Based on your 1100 sq. How many vents will my house need. The building requirements will probably tell you to place a certain number of soffit vents per square foot of ceiling space. And this guideline you ll need a minimum of.