The master bathroom and the 2nd bathroom vent through the roof and through the same opening.
How to vent a bath fan through the roof.
Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot.
Bathroom ventilation fan duct routing routing a bath vent duct down out or up through an attic or roof out.
Bend over the tabs then nail the tabs to the roof.
I recommend that my clients vent their bath fans out a gable wall if at all possible when not using an hrv or erv that is.
Take the end of the duct with the connector fitting and attach it to bath vent fan.
I would recommend installing a bath fan with a new vent that goes to the gable wall roof or even the soffit last choice.
This involves running ductwork from the fan usually though an attic and out through the roof.
In all cases the ducting needs to conduct the exchaust to the building exterior and needs to terminate in an animal proof vent cover.
You may just want to go with a completely new vent the whole way most modern bathroom fans require 4 or 6 vent hoses for much better performance and lower noise.
If you vent through a soffit where attic vents are often located the moisture will get sucked back up into the attic or roof venting.
The 2nd bathroom vent drips on the floor and is ruining the ceiling.
Next use aviation snips to cut slits into the sheet metal sleeve.
The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood.
It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly.
This article describes routing bath exhaust fan duct upwards through an attic or roof space or downwards through a floor or crawl space.
Pass the opposite end of the duct through the hole in roof.
Run a thick bead of tri polymer sealant along the underside of vent hood.
The 2 pipes one a 4 master and the other a 3 2nd do not go through the ceiling but into a common box that goes through the roof.
Vent your bath and kitchen exhaust fans through the roof through a special roof hood.