Two Bathroom Fans One Duct

Was replacing bathroom fan 1 and while it was disconnected from its duct pipe the fan in the bathroom 2 was on and.

Two bathroom fans one duct.

I m adding bathroom fans to two back to back bathrooms on a single story house. I just installed two panasonic bath fans in two adjacent rooms and joined them together in the attic it works fine with no backdraft from one fan to the other. Each fan has a 6 flexible duct so i m thinking they d connect to a y then exit the roof. The 2 fans have their own ducts but just before they vent out the roof their duct pipes are attached to a common duct upside down y which means they vent out the same hole in.

Rather than two cheap axial fans into one duct outlet how about two ducts into a more powerful centrifugal fan which is a bit more expensive but has a lot more oomph. If you have two bathrooms that are close together and one has an exhaust fan and the other doesn t you might be. One in line centrifugal fan can be mounted in the attic to exhaust the moisture from two bathrooms. Thanks for any info mike.

You should not put more than one fan into a common duct each fan should have its own duct run to atmosphere. Afaik if the fans you installed have built in dampers then you can wye them together and use one outlet without a problem. Each fan vents separately out the roof. The classic example occurs in multifamily units if one tenant is a smoker the tenant next door can smell tobacco smoke that enters the bathroom through the exhaust fan.

Each bathroom has its own exhaust fan. I felt air coming from bathroom 2 s fan down through the metal duct pipe for venting bathroom 1. Can they share one t top going out of the roof.