Bathroom Exhaust Into Attic

All municipalities have different requirements but some do not draw a hard line on requiring exhaust fans.

Bathroom exhaust into attic.

Bathroom vent fans are rated by how many cubic feet of air they can move in one minute known as the cfm rating. It s also important to note that if you install a roof vent cover for a clothes dryer you must remove the metal screen because it will catch lint and may turn into a fire hazard. 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. Bathroom code does address the issue of moving odor and moisture laden air from the bathroom to the outside.

Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof. On 2020 02 26 by mod bath exhaust vents need to be directed to the outdoors not just dumped anywhere inside the building. Bathroom ventilation codes require a bathroom exhaust fan to vent to the exterior not the attic for health and structural reasons. A bird s nest in a bathroom vent will greatly reduce or eliminate the effectiveness of a bathroom exhaust fan.

It may also violate a shingle warranty. In no case is it acceptable to just dump any exhaust fan directly into an attic. Anon if i understand your original question you have a bath exhaust that is discharging into a roof cavity or space not to outside. 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.

Bathroom exhaust fans perform an important function by removing excess moisture from your home. This involves running ductwork from the fan usually though an attic and out through the roof. 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. Surprisingly bathroom fans are not required by some building codes.

To determine which size fan to buy for your bath multiply the room s square footage by 1 1. It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly. Bathroom fan vent code requirements include no venting to attic areas to help reduce mold or structural problems.