Bathroom Ventilation Fan Into Attic

Draw a mark on the bathroom ceiling where you d like to install the vent fan.

Bathroom ventilation fan into attic.

Our article bathroom ventilation codes specs cites the importance of venting bath vent fans to the outdoors not into an attic or crawl space. You should never exhaust the bathroom fan directly into the attic. Bathroom fan vent code requirements include no venting to attic areas to help reduce mold or structural problems. Through the roof or an exterior gable wall.

For optimum performance locate it between the shower and the toilet. 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. The question about moist air reentering an attic through soffit vents after it has been blown out of an exhaust vent opening is a fair one but i don t think that s likely to be a significant building moisture source.

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. Options for venting a bathroom exhaust fan include best to worst. Use an extra long 3 8 inch diameter spade bit to bore a reference hole through the ceiling and into the attic. However you can vent a bathroom fan through an attic while it terminates on the roof or gable end.

Bathroom ventilation codes require a bathroom exhaust fan to vent to the exterior not the attic for health and structural reasons. No you should not vent a bathroom fan directly into an attic.