Can I install two separate 50cfm bath exhaust fans on one 4" vent duct? One is a tight half bath 7'x3' feet closed space. The other open standing shower 5' x 3'. both are in the same room 18'x14'. Straight line six feet apart will require one Y fitting down stream. Half bath is closer to outside wall. Both have separate fan switch.


1 Answer 1


You'll be much better off with one 100 CFM in-line duct fan downstream of the Y.

The fan that isn't operating will look like (and act as) an exhaust to the fan that is running.

If you desperately want two separate fans, run two separate ducts all the way outside.

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