Bathroom Exhaust Fan Goes Into Attic

It is because of this that many builders tend to advise against this method.

Bathroom exhaust fan goes into attic.

No you should not vent a bathroom fan directly into an attic. Proper bath fan exhaust. Mold is commonly found in attics with bath fans that exhaust moist air into the attic. If you have two bathrooms that are close together and one has an exhaust fan and the other doesn t you might be wondering if you can tie a new exhaust duct into the existing one.

It seems like such an easy solution just leave a bathroom vent hose in an attic. Climb into the attic and clear away any insulation from around the hole. No you cannot vent your bathroom exhaust fan into the attic. It can cause you a lot of problems with mold and mildew forming on the underside of your rafters and decking as well as getting into your insulation.

Mold can spread rapidly in an attic. In order to accomplish this the roof has to have a hole cut in it. This involves running ductwork from the fan usually though an attic and out through the roof. Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof.

For optimum performance locate it between the shower and the toilet. One attic mounted fan for two bathrooms one in line centrifugal fan can be mounted in the attic to exhaust the moisture from two bathrooms. Bath fans should always exhaust outside through the roof via insulated duct and terminate on a dampered roof cap. Click here to learn more about attic mold.

Dumping bathroom exhaust into an attic or under roof space invites costly mold contamination frost under the roof in freezing climates moisture damage to roof sheathing possibly even plywood delamination or rot roof failures and shorter roof shingle life. 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. Draw a mark on the bathroom ceiling where you d like to install the vent fan. No it s never a good idea to have any exhaust fan in your home dump all that hot moist air in your attic.

Several different ways you can move that hot air to the outside. Use an extra long 3 8 inch diameter spade bit to bore a reference hole through the ceiling and into the attic. It s all outdoor air anyways right. Your attic is not a temperature controlled environment is never the same temperature as your living space and generally closer to the temperature outside.

It cannot move air to a crawlspace or attic. However you can vent a bathroom fan through an attic while it terminates on the roof or gable end.