On Sat, 8 Mar 2014 23:05:34 +0000 (UTC), DerbyDad03
wrote:

If the calculations for a bathroom exhaust fan (cubic feet + equivalent
duct length) indicate an 80 CFM fan, is there any issue with using a 110
CFM fan?

Sure a bathroom fan can be too big. See those tornado pictures where
the house is flying away, or the Wizard of Oz. All of that because
the bathroom fans are too big.

Rural people who have never had a bathroom fan before get carried away
and buy a model much too big.