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Proper size for bath exhaust fan

I'm remodeling my bath and want to do the ventilation right.

The room is just under 8x8. The volume of the room is 481 cu ft. There is just one tub with a shower and a toilet.

Using the conventional method of calculating the fan size (divide the volume by 8) would call for a fan capable of at least 60 CFM.

The answer to my question may be obvious, but I'm going to ask it anyway. It would seem that an 80 CFM fan would be adequate, but is this a case where if 80 CFM is good, then a 100 or 110 CFM fan is better?
I can buy fans in this CFM range with a noise rating under 1 sone, and the price difference isn't that great so if bigger is always better then that's the way I want to go.
Thanks in advance.

Timothy Miller
Re: Proper size for bath exhaust fan

Hi, i'd choose the least noisy one the large fans just move more air faster. So if costs are the same my pick would be larger. I just installed a real quiet one with light combination cost $100 80 to 100 cfi. almost noisless.

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