Bathroom Exhaust Fan Vented Into Attic

This article describes routing bath exhaust fan duct upwards through an attic or roof space or downwards through a floor or crawl space.

Bathroom exhaust fan vented into attic.

This setup requires an in line centrifugal fan mounted in the attic drawing air simultaneously from both bathrooms see photo. Can you vent a bathroom exhaust fan into the soffit vents. If you vent the bathroom exhaust fan to close to the soffit vents which are vented plates under your homes outer edge and roof your home the air can be sucked right back into the attic from the soffit. Bathroom exhaust fans perform an important function by removing excess moisture from your home.

Also the installation of the bathroom exhaust fan will go much quicker if you ask a spouse or friend to help be in the attic while you work from below or to hand you tools while you re on. Bathroom fan vent code requirements include no venting to attic areas to help reduce mold or structural problems. I would by lying if i told you that it will cause problems it may be totally fine. No you cannot vent the bathroom exhaust fan into the soffit vents.

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. Never allow the duct to simply blow into an attic crawlspace or other enclosed area. The truth about attic bathroom venting. Bathroom ventilation fan duct routing routing a bath vent duct down out or up through an attic or roof out.

Note that the bathroom vent fan must always exhaust to the outdoors. But while you can t have two fans with one vent you can make one fan and one vent serve two bathrooms. In all cases the ducting needs to conduct the exchaust to the building exterior and needs to terminate in an animal proof vent cover. The lowdown on venting your bath fan into an attic is that it can be done but it should terminate on the outside.