This setup requires an in line centrifugal fan mounted in the attic drawing air simultaneously from both bathrooms see photo.
Roof venting a bathroom fan.
Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof.
Bathroom exhaust fan venting code summary section r303 3.
The truth about attic bathroom venting.
We explain how to install bathroom exhaust fans or vents the vent ducting the vent termination at the wall soffit or roof vent fan wiring bath vent duct insulation bath vent lengths clearances routing and we answer just about any other bathroom ventilation design or installation question you may have.
Options for venting a bathroom exhaust fan include best to worst.
This involves running ductwork from the fan usually though an attic and out through the roof.
In fact i have seen numerous houses that haven t yet had signs of mold with the bath fan venting incorrectly.
Slide a flat pry bar underneath the shingles around the nail to break the weather seal.
From the roof find the nail and use the utility knife to cut roof shingles from around the nail.
A grille in each bathroom attaches to ducts which then fasten to a y connector at the fan.
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.
When venting a bathroom exhaust fan make sure to vent the air to the outside rather than into your attic where it can cause mold and mildew to form.
It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly.
But while you can t have two fans with one vent you can make one fan and one vent serve two bathrooms.
Bathroom exhaust fans perform an important function by removing excess moisture from your home.
The lowdown on venting your bath fan into an attic is that it can be done but it should terminate on the outside.
If you vent through the roof condensation will drip back into the interior.
I would by lying if i told you that it will cause problems it may be totally fine.
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.
From inside the attic drive a nail through the roof directly above the bathroom vent fan.
Vent your bath and kitchen exhaust fans through the roof through a special roof hood.
Center the nail between two rafters.