Bathroom Fan Venting Into Attic

Example model ventilation codes.

Bathroom fan venting into attic.

Options for venting a bathroom exhaust fan include best to worst. It is because of this that many builders tend to advise against this method. See bathroom vent duct termination for details about how to terminate the bath exhaust vent duct. Through the roof or an exterior gable wall.

Bathroom fan vent code requirements include no venting to attic areas to help reduce mold or structural problems. You can find 4 in. An enclosed toilet would require its own exhaust fan exhaust fans approved for installation in wet areas would need to be located over or near the shower or tub bathroom doors should have at clearance to the floor. Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof.

This section notes that air exhausted from the bathroom must be sent outdoors not indoors to the same residence or indoors to any other dwelling unit. Duct already wrapped in insulation at home centers. No you should not vent a bathroom fan directly into an attic. There are several other factors to consider for proper ventilation such as.

Exhausting of the bath vent fan must indeed be to the building exterior. The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood. Both bathrooms are vented by a single in line fan that has one exhaust vent running through the roof. Although this isn t always possible in attic crawl spaces you should always insulate the duct to prevent condensation problems.

However you can vent a bathroom fan through an attic while it terminates on the roof or gable end. Exhaust air from toilet rooms and bathrooms shall not discharge into attic crawl space or other areas inside building. While this may seem obvious homeowners may out of convenience direct the vent into either of these locations. Bathroom ventilation codes require a bathroom exhaust fan to vent to the exterior not the attic for health and structural reasons.

In order to accomplish this the roof has to have a hole cut in it. Each bathroom has its own exhaust fan. It cannot move air to a crawlspace or attic. It seems like such an easy solution just leave a bathroom vent hose in an attic.

One in line centrifugal fan can be mounted in the attic to exhaust the moisture from two bathrooms.