How do Bathroom Exhaust Fans work

A bathroom fan is a type of fan that is installed in the bathroom and helps to remove excess moisture from the air. This will help to prevent mold and mildew from growing in the bathroom as well as prevent bacteria from developing.

Bonus takeaway, a great read” – after you read this post, we have prepared for you a fantastic summary with significant key takeaways below at the end of this page.

How do Bathroom Exhaust Fans Work This Way?…

If you are wondering what those fans are doing in your bathroom, then you have found the right page. Bathroom fans typically are installed in bathrooms with showers or bathtubs but can be installed anywhere that has high humidity levels.

What is a Bathroom Fan and Why Do You Need One?

A bathroom exhaust fan is a type of fan that helps to remove excess moisture from the air. Excess humidity can lead to mold or mildew growth and bacteria development. A bathroom exhaust fan can be installed anywhere there are high levels of humidity, such as a shower or bathtub, but they are most commonly found in bathrooms with showers or bathtubs.

What are the Different Types of Bathroom Fans?

Bathroom fans are one of the most important parts of a bathroom. They not only help to remove unpleasant odors but also provide relief from the humidity.

There are many types of exhaust fans you can choose from. Depending on your needs, you can choose from a range of different styles and sizes to suit your bathroom.

You have to know the pros and cons of each type before deciding which one is best for your home.

How to Choose the Best Bathroom Fan for Your Home or Business Needs?

When it comes to choosing a bathroom exhaust fan, there are many things that you need to consider. You need to know what size your bathroom is and how much power the fan needs. You also need to know what type of exhaust system you have or would like to install in your bathroom.

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The first thing that you should do is measure the size of your bathroom and then calculate the square footage. This will help you figure out what size venting system you will need for your bathroom. In addition, this will help you figure out how powerful of a fan you need.

The higher the square footage, the more powerful a fan will be needed in order to move all of the air through it quickly enough so as not to make it feel stuffy and humid inside of the room.

It’s time for you to know how bathroom fans work and appreciate their important function in keeping your bathroom well ventilated and your health risk-free.

Bathroom fans aren’t installed to keep you cool while showering or doing your other business. They are intended to remove the moisture and humidity that cause foul odors or mold buildup. Because your shower area is a damp place, it is prone to being a breeding ground for bacteria. So, the best way to maintain the air quality and cleanliness of your bathroom is to install ventilation systems like a bathroom or exhaust fan.

Today’s bathroom fans are more than just fans or rotor blades. Now, they are electrically powered with AC or DC motors that ensure consistent operation day in and out. Aside from this, they are quieter and more efficient in exhausting humidity and improving airflow.

Most manufacturers also make bathroom exhaust fans aesthetically pleasing, complementing wall decorations. Some even include a light bulb to add brightness to the room.

Aside from bathrooms, this type of exhaust fan also contributes to maintaining the air quality of the entire house. If all bathrooms in your house have bathroom fans, the humid air or smell can be expelled outside the house in no time. Of course, the effectiveness depends on how powerful they are.

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In summary, here are the purposes of bathroom fans:

  • To remove moisture and humidity
  • To eliminate smelly bathroom odors and air pollutants
  • To prevent water vapor that accumulating on the walls and mirror
  • To improve the overall air quality of the bathroom and home

How Bathroom Fans Work

The simplest way to explain the operation is to know the role of each part. Every bathroom fan has a motor, a fan, and a vent; these are essential parts that need to be present in a unit to guarantee successful ventilation. The motor needs an electric supply to power the fan. As the rotor blades spin, moisture is drawn up and is exhausted through the vent hood. This will continue as long as the bathroom fan is plugged in or turned on.

The effectivity of the fan depends on the power, which is rated in cubic feet per minute or CFM. This is the measurement of the airflow capacity of how much the fan can draw moisture from the room in a specified period of time.

Thus, it means that the higher the CFM rating, the more air is exhausted and the faster the airflow is. So, if you have a big room, you should get a bathroom fan with a high CFM rating.


As a general guideline, one CFM is equivalent to one square foot of the room. For a 100-square-foot bathroom, you should get a 100 CFM exhaust fan. For bathrooms with a standard toilet, bathtub, and shower, an additional 50 CFM is needed to ensure proper ventilation since these fixtures are always damp or wet.

For this reason, purchasing a bathroom fan with the right size and specifications is crucial. If the power rating is too low for the size of the room, moisture and odor won’t be effectively eliminated.


The old-style exhaust fans in the bathrooms are noisy, yet they are not properly doing their jobs. Today, you will find that electrically powered fans are more effective. However, the thing about powerful motors is that they are still noisy. And if they are not noisy, it means that they are not exhausting air at all.

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That’s why manufacturers integrate such kinds of technology to minimize the sound the motor produce. The noise of a bathroom fan is measured in sones. A good one has an average rating of 1.5 to 2.5 sones. Anything that goes beyond that will be disturbing to the ears.

Installation options

This type of appliance comes in different shapes and sizes. They can be mounted on the ceiling, or walls, or installed inline. All have their own pros and cons in terms of aesthetic design and performance. Aside from this, some bathroom fans can either have a simple switch for turning on and off or a timer, exhausting moisture after you take a shower.

Other tips:

  • Existing Wiring: Consider installing a fan with light over an existing light fixture for easier wiring and convenience.
  • Safety Ratings for Shower + Tub Fans: If you’re installing the fan over a shower/tub combo, make sure it’s safety certified for this location (typically, UL-listed).
  • Professional Installation: For safety, consider hiring an HVAC technician to install your fan and/or an electrician to perform wiring requirements if you need assistance.

Summary Page & Key Takeaways

🚽 A bathroom fan is installed in the bathroom to remove excess moisture from the air, preventing mold, mildew, and bacteria growth.

🌬️ Bathroom fans help improve air quality and eliminate unpleasant odors in the bathroom.

💡 Modern bathroom fans are electrically powered with AC or DC motors, quieter, and more efficient in exhausting humidity.

🏠 Bathroom fans contribute to maintaining the overall air quality of the home by expelling humid air and odors outside.

📏 The power of a bathroom fan is measured in cubic feet per minute (CFM), and a higher CFM rating indicates faster and more effective airflow.

🔉 Noise levels of bathroom fans are measured in sones, with a good rating ranging from 1.5 to 2.5 sones.

🛠️ Bathroom fans can be mounted on ceilings, walls, or installed inline, and they come with various installation options and features like timers.

⚡ Existing wiring can be utilized for easier installation of a fan with light.

⚠️ Safety certification is important when installing a fan over a shower/tub combo.

🧹 Other related topics on the website include cleaning toilet brushes, effective toilet cleaning, and cleaning a toilet tank.