How To Vent A Bathroom Fan Through Attic

The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood.

How to vent a bathroom fan through attic. From outside use 4 inch hole saw to cut hole for wall cap. 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. Bathroom vent fans are rated by how many cubic feet of air they can move in one minute known as the cfm rating. Either way the vent will have to go directly to the outside and installed with a vent hood cover.

The correct way to vent a bathroom fan through an attic is to terminate the vent either to the roof or to the gable wall. Bathroom ventilation fan duct routing routing a bath vent duct down out or up through an attic or roof out. No you cannot vent the bathroom exhaust fan into the soffit vents. Vent your bath and kitchen exhaust fans through the roof through a special roof hood.

This article describes routing bath exhaust fan duct upwards through an attic or roof space or downwards through a floor or crawl space. The 2 pipes one a 4 master and the other a 3 2nd do not go through the ceiling but into a common box that goes through the roof. This involves running ductwork from the fan usually though an attic and out through the roof. In all cases the ducting needs to conduct the exchaust to the building exterior and needs to terminate in an animal proof vent cover.

This will serve as a reference point for positioning the wall cap. Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot. In this video this old house general contractor tom silva explains how to vent a bathroom fan. Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof.

The bathroom here is below an accessible attic so tom ran the exhaust duct across the attic and out a gable end. It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly. The master bathroom and the 2nd bathroom vent through the roof and through the same opening. To determine which size fan to buy for your bath multiply the room s square footage by 1 1.

The 2nd bathroom vent drips on the floor and is ruining the ceiling.