How To Choose A Bathroom Vent Fan

Average Costs For:
Most Homeowners Spent Between: Most People Spent: $5,350 - $13,670
Low End
High End

See costs in your area Start Here - Enter Your Zip Code

Bathroom Vent FanYour bathroom is the dampest room of the house. Without a strong vent fan, this excessive moisture creates a lot of problems. These include: mold and mildew, unpleasant odors, poor air quality, long-term damage to building materials, such as paint, drywall, and framing. Consequently, repairs and renovation will be very costly.

All of this can be easily avoided by installing a high quality exhaust fan. Even you have a window in your bathroom, it is still important to also have a vent fan. For bathrooms that don’t have windows, a vent fan is a MUST.

Here is how you pick a model that will work for your bathroom and your budget.

Vent Type

It is important to pick a vent fan that will be best suited for your particular bathroom (location, duct work configuration, etc)

There are 3 types of bathroom vents:

inline bathroom vent fanCeiling-mounted: this is the most common type of a bathroom vent. It is installed into the ceiling and vents to the outside via the ducts or through the roof.

Wall-mounted: this vent is installed in an exterior wall and pulls the air directly outside. The biggest advantage of these models is that they don’t require duct work. Keep in mind, that many will have a visible register.

Inline/Remote: this vent can be installed either in the ceiling or wall. Here, the motor is positioned between ducts and pulls the air to the outside remotely. An inline model is a good choice if you want to have multiple fans in one large bathroom. A single inline fan can also be used in multiple bathrooms.

Ventilation Power

Proper amount of airflow is key to having a vent fan that will actually get rid of excess moisture and odors. The airflow rating is measured in cubic feet per minute (CFM). The bigger your bathroom, the higher CFM rating you want the exhaust fan to have. If you get a fan that is not powerful enough, you will simply be wasting electricity.

Here is how to determine exactly how many CFM’s will do the trick in your bathroom.

1. Measure the bathroom area

2. According to the Home Ventilating Institute, you need to have one CFM per square foot of bathroom area. So if your bathroom is 8×10 sq.ft., you need a vent fan with 80 CFMS.

3. In any size bathroom, there needs to be a vent fan with minimum of 50 CFM.

4. If your bathroom is 10×10 (100 sq.ft.) or larger, it is recommended to add 50 CFM for each toilet, another 50 CFMs for each bathroom/tub combination, and another 100 CFMs for a whirlpool/jacuzzi tub. This means that you will need a fan with at least 200 CFMs in a large bathroom.

5. If the ceilings in your bathroom are taller than 8 ft. you will need a higher CFM rating.

Noise Level

If the bathroom is your relaxation haven, you certainly want it to be quiet. Bathroom fan noise is rated in sones, so you should look for a model with a low rating (range is >1 to 5 sones). One sone sounds like a quiet kitchen refrigerator. So if you want the vent to be almost silent, you need a 1 sone rating or less. A model with 2 sones is a good standard for quiet operation. Anything above 3 will produce easily detectable noise and can be perceived as intrusive.


Modern bathroom vent fans come jam picked with features. However, unlike in many other appliances, many of these features are actually very useful. Here are some great ones to consider:

Integrated Light: this is very convenient, especially in smaller bathrooms, where you don’t want too many fixtures on the ceiling. Many light + fan models are very stylish.

Night Light: this vent can help provide illumination at night without needing to turn on the main light.

Multi Speed Setting: some more expensive multi-speed fans allow you to select the CFM rating that you want, depending on your needs.

Integrated Heater: an exhaust with a heater can add extra comfort to your bathroom during cold seasons. These models can heat up in as fast as 1 minute, for immediate warmth and comfort.

Fans with Humidity and Motion Sensors : these fans can be highly effective. A humidity sensor automatically triggers the fan to turn on when humidity rises above a certain level and turn off when humidity level is reduced. A motion sensor detects when someone goes into the bathroom and turns on the fan or light only.

Energy Efficiency

Look for an EnergyStar-rated energy saving vents to reduce spending on electricity. Some energy star rated fans can be as much as 70% more efficient than their competitors.

Heat Exchanger Vent Fan

One factor that is often overlooked is that a strong vent fan will suck a lot of heated air out of your house. To prevent this from happening you can install a heat exchanger vent fan. What these models do is use warm outgoing air to heat cooler, incoming replacement air.The only downside is that these heat exchange vents are at least twice as expensive as regular models.

Choosing the Proper Bathroom Vent Fan for your house:

Watch this very detailed video for more insights into what you should know about choosing the right vent for your bath:

Professional Installation

You will most likely require the help of a professional to install your new exhaust fan. Typically, HVAC contractors charge anywhere from $200-600 depending on the complexity of your particular installation.

You need to make sure to specify to the installer that the bathroom exhaust fan must be connected to vent ducts that will channel the air to the outside of your home. Unfortunately, too often the ventilation is set up the wrong way and can cause serious long-term damage. If the bathroom is located on the first floor, the fan is set up to exhaust air into the space between the ceiling joists. If the bathroom is located on the floor below the roof/attic, the fan is set up to exhaust air into the attic.

Both are completely unacceptable methods of installation, because this cold, moist air condenses in these dark closed off spaces, causing mold, and damaging floors, walls, and framing.

About Yelena G

Yelena G. has been working in the remodeling and construction industry for over 15 years. Her focus is on construction planning and design as well as project cost estimating. Yelena also has a personal interest in interior design, as well as in unique DIY remodeling projects. Read more about Yelena

Leave a Reply

One comment on “How To Choose A Bathroom Vent Fan