2 4" bathroom fans to same exit vent?

Old 02-12-20, 07:23 AM
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2 4" bathroom fans to same exit vent?

Is it possible to run 2 bathroom extractor fans to the same exit vent?
Old 02-12-20, 07:27 AM
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No, they both need there own vent.
Old 02-12-20, 08:44 AM
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I agree, however...
FWIW...refer to recent posting
Exhaust fan venting
Old 02-12-20, 03:28 PM
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I doubt there is a flow issue, but a possibility the flow from one would end up in the other which defeats the purpose of the fan!
joecaption voted this post useful.
Old 05-01-20, 08:48 AM
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2 fans one bathroom?

I get the problem with 2 fans in separate bathrooms. I want to have two fans in the same bathroom, both on the same wall switch. Is it ok if I run the 4 inch flexible vent tubes into a y with a 6 inch exit tube to a 6 inch roof vent. All this on a short run from fans to roof.
Old 05-01-20, 09:03 AM
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If they are coming off the same switch, a 6" vent should be fine. Make sure to use a wye and not a tee.

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