Bathroom Ventilation Fan Into Attic

Through the roof or an exterior gable wall.

Bathroom ventilation fan into attic. Bathroom fan vent code requirements include no venting to attic areas to help reduce mold or structural problems. Options for venting a bathroom exhaust fan include best to worst. Climb into the attic and clear away any insulation from around the hole. For optimum performance locate it between the shower and the toilet.

No you should not vent a bathroom fan directly into an 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. Bathroom ventilation codes require a bathroom exhaust fan to vent to the exterior not the attic for health and structural reasons. Draw a mark on the bathroom ceiling where you d like to install the vent fan.

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. It seems like such an easy solution just leave a bathroom vent hose in an attic. Use an extra long 3 8 inch diameter spade bit to bore a reference hole through the ceiling and into the attic. No you cannot vent your bathroom exhaust fan into the attic.

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. However you can vent a bathroom fan through an attic while it terminates on the roof or gable end.