How To Vent Bathroom Fan Through Wall

In this video this old house general contractor tom silva explains how to vent a bathroom fan.

How to vent bathroom fan through wall. This will serve as a reference point for positioning the wall cap. It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly. However venting through the wall is considerably less risky. Through the roof or an exterior gable wall.

If you vent through a soffit where attic vents are often located the moisture will get sucked back up into the attic or roof venting. A 3 or 4 inch duct connects to the outlet on the fan housing and runs to a side wall or to the roof and connects to a vent cap that allows the. The fan can be vented either through the ceiling or wall. Behind a soffit vent.

A down through soffit exhaust vent design by leaving warm air in the exhaust duct when the fan is off creates a heat trap that reduces heat loss out of the bathroom through the exhaust fan duct when the fan is off in comparison with up routed vents or even horizontal vents through a gable end wall. Installing a bath fan through a wall isn t that difficult of a job if you have the right tools. If you vent through the roof condensation will drip back into the interior. If you want to vent a bathroom fan through an exterior wall you will have to cut a 3 inch or 4 inch hole with a hole.

From outside use 4 inch hole saw to cut hole for wall cap. I recommend that my clients vent their bath fans out a gable wall if at all possible when not using an hrv or erv that is. Drive nail through house wall from attic. Keep the run of vent pipe as short and straight as possible.

Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof. For example a 100 square foot bath would require a 110 cfm rated fan. To improve venting and reduce air resistance in the vent pipe. 1 climb into the attic and locate the bath fan.

Bathroom vent fans are rated by how many cubic feet of air they can move in one minute known as the cfm rating. Behind a gable vent. Options for venting a bathroom exhaust fan include best to worst. This involves running ductwork from the fan usually though an attic and out through the roof.

Fans also have a sound rating measured in sones. To determine which size fan to buy for your bath multiply the room s square footage by 1 1.