FullCalculator

Exhaust / Bathroom Fan Sizing Calculator

Exhaust Fan by Room Type

Size an exhaust fan based on room type and dimensions

Kitchen Range Hood

Size a kitchen range hood exhaust fan

Formula

CFM = (Room Volume x ACH) / 60 | Kitchen Hood CFM = Range Width (ft) x 100 x Fuel Factor

Frequently Asked Questions

What size exhaust fan do I need for my bathroom?
The HVI (Home Ventilating Institute) recommends 1 CFM per square foot of bathroom floor area, with a minimum of 50 CFM. For an 8x10 bathroom, you need at least an 80 CFM fan. Bathrooms with a jetted tub should add 50 CFM extra.
How loud are exhaust fans?
Fan noise is measured in sones. Below 1.0 sone is nearly silent. 1.0-2.0 sones is quiet and comfortable for bathrooms. 2.0-4.0 sones is moderate. Above 4.0 sones is noticeable. Look for fans rated at 1.0 sone or less for bedrooms and bathrooms.

You may also need