How To Vent Bathroom Fan Through Wall

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.

How to vent bathroom fan through wall.

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. Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof. 1 climb into the attic and locate the bath fan. Fans also have a sound rating measured in sones.

The bathroom exhaust ventilation fan disperses air through an opening in the fan housing which is usually 3 inches in diameter and ideally faces in the direction of the ventilation system outlet. Behind a gable vent. Drive nail through house wall from attic. Options for venting a bathroom exhaust fan include best to worst.

However venting through the wall is considerably less risky. 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. Behind a soffit vent. To determine which size fan to buy for your bath multiply the room s square footage by 1 1.

This will serve as a reference point for positioning the wall cap. To improve venting and reduce air resistance in the vent pipe. In this video this old house general contractor tom silva explains how to vent a bathroom fan. 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.

For example a 100 square foot bath would require a 110 cfm rated fan. It can probably be done in an afternoon if you are organized for the job but it may take a weekend if you aren t fully prepared. This involves running ductwork from the fan usually though an attic and out through the roof. From outside use 4 inch hole saw to cut hole for wall cap.

Since a bathroom vent fan should run for 10 15 minutes after you finish your shower to remove all the moisture consider a fan that cuts on and off automatically using a moisture sensor or replace the wall switch with a timer. Keep the run of vent pipe as short and straight as possible. Bathroom vent fans are rated by how many cubic feet of air they can move in one minute known as the cfm rating. Installing a bath fan through a wall isn t that difficult of a job if you have the right tools.

It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly. The fan can be vented either through the ceiling or wall.