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## Exhaust Fan Formula

Is there any formula in selection of a exhaust fan in order to meet the requirement of a certain room or area? Shall we say bathroom or kitchen. Thanks for help.

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## A "rule of thumb"

would have you figure the total cubic feet of air in the space and then figure how much exhaust you need to change that air X times Fill in for X 3 to 7 air changes

So room volume times air changes divided by 60 will give you CFMs of exhaust

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How could you determine the total cubic feet of air in that space? Is there any standard to be follow or table in reference of any space regarding with the cubic feet of air in it? Thanks ahead

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Originally Posted by zero13
How could you determine the total cubic feet of air in that space? Is there any standard to be follow or table in reference of any space regarding with the cubic feet of air in it? Thanks ahead
(L X W X H = CF)

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Originally Posted by zero13
Is there any formula in selection of a exhaust fan in order to meet the requirement of a certain room or area? Shall we say bathroom or kitchen. Thanks for help.
International Mechanical Code section 4 will give you the ventilation rates that are required for specific applications.

Length times width times height equals cubic feet.

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Thanks people, i just thought that there are standard for any specific rooms to be follow. thank so much to everyone.

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