Bathroom vent exhausting into attic space.
Best way to vent bathroom fan in attic.
If you vent through the roof condensation will drip back into the interior.
Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot.
Vent your bath and kitchen exhaust fans through the roof through a special roof hood.
The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood.
These stem vents should be properly connected to the bathroom ducts to ensure that moisture is traveling to the exterior not the attic space.
In order to accomplish this the roof has to have a hole cut in it.
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.
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.
This involves running ductwork from the fan usually though an attic and out through the roof.
Through the roof or an exterior gable wall.
This setup requires an in line centrifugal fan mounted in the attic drawing air simultaneously from both bathrooms see photo.
Either way the vent will have to go directly to the outside and installed with a vent hood cover.
To be properly terminated bathroom fans should exit the home through stem vents that are specifically used for this purpose.
But while you can t have two fans with one vent you can make one fan and one vent serve two bathrooms.
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.
The correct way to vent a bathroom fan through an attic is to terminate the vent either to the roof or to the gable wall.
Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof.