Bathroom Vent Discharge Into Attic

Health and structural issues when a bathroom is not vented properly.

Bathroom vent discharge into attic.

Leaking and damaged vents as well as improperly installed ones also can cause problems. This involves running ductwork from the fan usually though an attic and out through the roof. Sizing a bathroom fan can be somewhat tricky as the information out there is all over the place. Each fan vents separately out the roof.

Each bathroom has its own exhaust fan. Exhaust air from toilet rooms and bathrooms shall not discharge into attic crawl space or other areas inside building. It may also violate a shingle warranty. Both bathrooms are vented by a single in line fan that has one exhaust vent running through the roof.

M1507 2 exhaust air from bathrooms and toilet rooms shall not discharge into an attic crawl space or other areas inside the building. Exhausting of the bath vent fan must indeed be to the building exterior. Your attic is not a temperature controlled environment is never the same temperature as your living space and generally closer to the temperature outside. Through the roof or an exterior gable wall.

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. M1501 1 air shall not be exhausted into an attic soffit ridge vent or crawl space. It is because of this that many builders tend to advise against this method. The bath should be vented by either a 20 cfm continuous vent fan or a 50 cfm vent fan that is intermittent or switched.

That will take it from the bath exhaust fan to a discharge point. The exhaust needs to vent outdoors. In order to accomplish this the roof has to have a hole cut in it. Options for venting a bathroom exhaust fan include best to worst.

Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof. So what you want to do is you want to install a duct a vent duct and you can use flex duct for this. A lot of options. 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.

Allowing the exhaust to vent into your attic can potentially cause several moisture problems. The next thing you need to do is make sure the exhaust is successfully making its way out of your home. One in line centrifugal fan can be mounted in the attic to exhaust the moisture from two bathrooms. If you re simply replacing the fan the ducts should already be set up for you.

You should never exhaust the bathroom fan directly into the attic.