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Do Bathroom Exhaust Fans Need to be Vented to the Outside?

When you're thinking of installing a new bathroom exhaust fan, the question of where the air is going to go is a very important one. Does it need to be vented to the outside of the house or building, or can you just move it outside of the bathroom?

Venting to the Outside is Typically Considered Mandatory

Even though it's tempting to vent a bathroom fan into the attic, there are several problems with this method. One of the main ones is that it brings too much moisture into a space that is meant to be dry. This can get mold started in the insulation, rot roof timbers, and otherwise cause serious problems. Because of this, many areas have building codes that require outside venting for bathroom exhaust fans.

Where Should the Bathroom Fan's Vent Outlet be Placed?

Since the attic is not a suitable location for your bathroom fan's vent, the next question is where that vent should be located. Even though the roof is the most obvious spot - and it is possible to run a vent duct to go out there  - it is actually not the preferred place for the vent opening. Openings in roofs often lead to leaks, so they should be avoided when possible. This is true even if you already have a chimney or other item in your roof. More roof holes mean more chances for problems.

Because of this, the preferred location for an exhaust vent is the side of your home or building. Openings in walls rarely collect water, and they can be hooded to provide further protection.

Do You Need a Different Fan Style Depending on Where the Vent Goes?

Fans are connected to ductwork, so you don't need a different style for a different vent location. Instead, choose the style that matches where you're going to install the fan itself. Most bathroom fans are meant to be installed in ceilings, so if you want to put the fan itself into a wall, you'll need a sidewall bathroom exhaust fan. Like ceiling-mounted fans, these have connections that vary depending on the size of the ductwork they'll attach to.

What Other Choices Need to be Kept in Mind?

As with most other products, there are multiple manufacturers to choose from. One of the big ones is Solar & Palau, which makes many models that do away with the traditional grating and that look like can lights. These are great for installations where you don't want the look of a bathroom fan, but still want the functionality of one. This company also produces commercial bathroom exhaust fan options, which have a more traditional look.

Another important manufacturer is Continental Fan, which makes fans with gratings that blend in better with white and off-white ceilings. They also produce fan motors that fit inside existing ductwork to make the ducts do double duty without the need to install more gratings. These versatile motors make it easy to add ventilation to any area that already has duct outlets.

With all of these options, one thing remains the same: The moist air does have to go to the outside. Make sure to follow this guideline to avoid mold and rot issues in your structure.

Industrial Fans Direct carries a varied selection of bathroom exhaust fans, suitable for most commercial and residential properties. 

Other Resources to Check Out:

What is the Best Bathroom Exhaust Fan?

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