3 x 320 cfm 960 cfm to be vented.
Bathroom exhaust fan vent pipe size.
You can upgrade to a larger diameter duct for greater efficiency or you can use an adapter reducer often included with the fan to fit the smaller duct.
A 3 or 4 inch duct connects to the outlet on the fan housing and runs to a side wall or to the roof and connects to a vent cap that allows the exhaust to disperse outdoors.
The bathroom exhaust ventilation fan disperses air through an opening in the fan housing which is usually 3 inches in diameter and ideally faces in the direction of the ventilation system outlet.
If your bathroom has a higher ceiling multiply the width x length x height of the room divide by 60 minutes in an hour then multiply by 8 number of air exchanges per hour.
Why your bathroom should have an exhausting vent fan bathroom venting fans are about more than just eliminating noxious odors.
For that air volume 8 diameter vent ducts are close to their limit and 10 is indeed preferable.
The bathroom has a separate toilet room.
A diameter of 4 inches is common for exhaust ducts but some high cfm fans fit a 6 inch diameter duct.
100 cfm fan with a 4 exhaust port and back flow flap.
Required bathroom vent fan ventilation rate in cfm this ventilation code specifies a bathroom exhaust airflow rate for toilet rooms and bathrooms not served by a window of adequate size of 25 or 50 cfm ft for hotels motels resorts and dormitories and a slightly more modest 20 50 cfm for private dwellings.
The second fan is 150cfm with the ability to have a 4 or 6 vent pipe attached.
25 8 200 cfm rated vent fan.
Therefor there are two fans.
If i can find a y pipe with a 4 and a 6 entry what size should the exit pipe be.
The basics of venting a bathroom exhaust fan.
The minimum allowed fan size is 50 cfm so if your bathroom is for example only 42 square feet you still need a 50 cfm fan.
For example a 10 wide by 15 long bathroom with a 10 ceiling would need.
Your inline exhaust fan has to thus be have a 960 cfm capacity before allowing for losses due to duct size bends material restrictions in air flow and duct length.
1500 60 25.