Bathroom Exhaust Fan: What to Know About?

Written By Adam Paul - Waterproofing Expert

A bathroom exhaust fan is a mechanical ventilation device with rotating blades that create a current of air or moisture for cooling or ventilation in the bathroom. Bathroom exhaust fans can increase the ventilation in the bathroom by removing excess moisture. This helps to improve the air quality in the bathroom and minimize water problems in the bathroom.

Sone rating and CFM are important when selecting a bathroom exhaust fan. Sone rating of the bathroom exhaust fan is used to measure the loudness while CFM rate is used to measure the flow rate. The lower Sone rate and higher CFM bathroom exhaust fans are good for a bathroom.

Bathroom exhaust fans are available in different types according to their mounting types. Ceiling-mounting and wall-mounting exhaust fans are the most used exhaust fans in the bathroom.

A bathroom exhaust fan can consume 10-50 watts. The fan can be operated with DC voltage. It can be operated even using the batteries during a power cut. A regular bathroom exhaust fan has 900 to 2,500 RPM. The higher RPM, torque is essential for the CFM rate.

Bathroom exhaust fans consist of additional features such as light, LED bulbs, Bluetooth, speakers, and heaters. All of these additional features increase the user experience of the bathroom user and reduce the human operation to the bathroom. Bathroom fans consist of sensors which help to automate most of the human function itself.

If a bathroom exhaust fan tends to open the direct water flow it can be damaged. But it is not damaged by the higher humidity level in the bathroom.

What is a Bathroom Exhaust Fan?

A bathroom exhaust fan is a mechanical ventilation device with rotating blades that create a current of air or moisture for cooling or ventilation in the bathroom. Bathroom exhaust fan is specially designed to remove excess moisture, odors, and airborne contaminants from the bathroom. 

The advantages of using a bathroom exhaust fan are increasing ventilation in the bathroom, removing humid air, depleting the bathroom of excess moisture, cooling down the bathroom after the hot shower, and removing pollutants and allergens from the air. 

The benefits of using a bathroom exhaust fan are maintaining fresh air in the bathroom, preventing mold and mildew growth, preventing water damage in bathroom surfaces and fixtures, cooling the bathroom, improving air quality, and reducing structural issues in the bathroom.

What is Sone Rating?

Sone rating is a measure of the loudness or noise level produced by a bathroom exhaust fan. Sone rating explains how quiet or noisy a bathroom fan will be during operation. The sone rating scale starts at 0.5 sones for an extremely quiet fan and goes up from there. If the sone rating is high it means the bathroom ventilation fan produces higher noise. 

Sone rating helps consumers choose an exhaust fan that won't disturb their ears ensuring that the fan operates smoothly without creating excessive noise. Below is the Sone rating and its noise level comparison in real environment.

• Sone rating 1 is equal to 28 Decibles and it is similar to the hum of refrigerator noise
• Sone rating 2 is equal to 37.99 Decibles and it is similar to a quiet office
• Sone rating 3 is equal to 43.84 Decibles and it is similar to a normal conversation
• Sone rating 4 is equal to 47.99 Decibles and it is similar to TV or radio
• Sone rating 5 is equal to 51.21 Decibles and it is similar to a busy restaurant

So you should choose a bathroom fan with a lower Sone rating. It will make a calm and quiet place in the bathroom.

What is the CFM Rate in a Bathroom Exhaust Fan?

CFM, or cubic feet per minute, is a measure of the airflow capacity of a bathroom exhaust fan. It indicates how many cubic feet of air in the bathroom can move per minute. A higher CFM rating can blow and ventilate a larger volume of air from the bathroom. It helps to effectively deplete moisture, remove odors, and refreshing the air in the bathroom.

Choosing a fan with a higher CFM rating helps to ensure optimal performance for your bathroom. A higher CFM-rated bathroom exhaust fan is more effective at maintaining air quality, preventing mold and mildew build-up, and keeping the bathroom comfortable by acting as an air cooler.

What are the Bathroom Exhaust Fan types and their Advantages?

These are the 4 different types of bathroom exhaust fans and their advantages.

1. Ceiling-mounted exhaust fan: Ceiling-mounted exhaust fans in the bathroom helps to ventilate the entire room directly through the ceiling. It efficiently depletes moisture and unpleasant smells. Ceiling-mounted exhaust fans are ideal for bathrooms with attic space, allowing the air to blow out above, keeping the bathroom fresh without draining energy.
2. Wall-mounted exhaust fan: Wall-mounted exhaust fans help to ventilate bathrooms where ceiling installation isn’t possible. It is installed on the wall. Wall-mounted exhaust fand can directly expel air outdoors.
3. Inline exhaust fan: Inline exhaust fan helps to reduce noise while efficiently ventilating multiple areas. Installed in a duct system, it draws air from the bathroom and other spaces.
4. Combination exhaust fan with light/heater: A combined bathroom exhaust fan helps to ventilate the bathroom while providing additional lighting and warmth. It’s a multipurpose solution, keeping the air refreshed, preventing mold, and serving as an air cooler during warmer months

What size of Bathroom Exhaust Fan is Good?

The size of the bathroom exhaust fan can be measured by the CFM value. CFM denotes the airflow capacity of the bathroom exhaust fan. This measurement indicates how much air the fan can move within a minute, helping to deplete moisture, ventilate the space, and refresh the bathroom air. CFM depends on factors such as fan blade diameter, RPM of the motor, and torque of the motor. 

When you choose a bathroom exhaust fan you should always choose a bathroom exhaust fan with the appropriate size and flow rate. It will work efficiently to ventilate the bathroom area without any troubleshooting. It provides long-lasting performance that protects both the bathroom and its occupants.

How much Power is Needed for the Bathroom Exhaust Fan?

The power needed for a bathroom exhaust fan typically ranges between 10 to 50 watts. The bathroom exhaust fan power depends on the fan's size and capacity. Higher-wattage exhaust fans are necessary for longer duct systems. Higher-wattage fans can handle more significant ventilation needs in bigger bathrooms.

Bathroom exhaust fans are usually powered by a standard electrical connection, using 120 volts as the power source. In some cases, bathroom exhaust fans can be operated through solar panels in order to reduce energy consumption and provide an eco-friendly way to keep the bathroom air fresh and cool.

How many Volts are needed for the Bathroom Exhaust Fan?

Most of bathroom exhaust fans typically need 120 volts (120 V) of alternating current (AC) to operate effectively. The higher voltage-rated bathroom exhaust fans have higher RPM. Higher voltage bathroom exhaust fans have a higher CFM rate which helps to increase bathroom ventilation quickly.

In some special cases, bathroom exhaust fans can use DC voltage also. DC voltage is used in more energy-efficient models, usually operating at lower voltages, such as 12 or 24 volts. DC-powered fans are often quieter and can be connected to solar power systems, making them an eco-friendly option for maintaining air quality in the bathroom.

Can Bathroom Exhaust Fans Operated by Batteries?

Yes, bathroom exhaust fans can be operated by the batteries because most of bathroom exhaust fans can be operated by the DC current. Hence you can use a 12V battery to operate the bathroom exhaust fan even during the power cut. 

As well as these fans can be operated by rechargeable batteries and solar systems where access to a direct power source is limited or during power outages. This helps to blow out moist air, reducing the risk of mold and mildew and maintains a comfortable environment without wearing out the fan. 

How much RPM is Good for a Bathroom Exhaust Fan?

RPM, or revolutions per minute, is a measure of how many times the fan's blades rotate in one minute. A typical bathroom exhaust fan operates at an RPM range of around 900 to 2,500. In a bathroom exhaust fan, RPM is an important factor that determines the fan's speed and efficiency in depleting moisture and ventilating the bathroom. 

The connection between RPM, torque, and flow rate is essential for the fan's CFM rate. Higher RPMs generally mean the fan blades spin faster, which can increase the flow rate. It allows fan to blow air more effectively out of the bathroom. Lower RPM does not drain out the excess moisture in the bathroom soon. Hence higher RPM is always important for bathroom ventilations.

What are the Essential Features of a Bathroom Exhaust Fan?

Here are the essential features of a bathroom exhaust fan and their importance:

1. Bathroom exhaust fan with light: Bathroom exhaust fan with light combines ventilation with lighting. It ensures that the air is ventilated while providing adequate lighting, preventing the bathroom from wearing out due to poor air quality. This is highly recommended for smaller bathrooms where space is limited.
2. Bathroom exhaust fan with LED Light/Night Light: Bathroom exhaust fan can be equipped with energy-efficient LED lighting. This feature ensures the bathroom is well-lit while also providing a soft night-light for night time use.
3. Bathroom exhaust fan with Bluetooth: The Bluetooth feature in the bathroom exhaust fan allows you to connect your devices wirelessly, providing entertainment while you shower or get ready. It combines the function of an exhaust fan with modern convenience, ensuring the air is refreshed while you enjoy your favourite music or podcasts.
4. Bathroom exhaust fan with speaker: The speaker feature in the bathroom exhaust fan can enhance your bathroom experience. It ventilates the bathroom while allowing you to listen to music, making your routine more enjoyable without compromising air quality.
5. Bathroom exhaust fan with remote: The remote control feature in the bathroom exhaust fan offers remote control operation, allowing you to adjust the fan’s settings from a distance. It provides convenience and ensures that the fan can ventilate and refresh the air efficiently.
6. Bathroom exhaust fan with heater: The bathroom exhaust fan with heater includes a built-in heater, which helps to warm the bathroom quickly during colder months. It depletes the need for separate heating systems, keeping the bathroom air warm and comfortable while still ventilating to prevent moisture build-up.
7. Bathroom exhaust fan with heat lamp: The heat lamp in the bathroom exhaust fan provides targeted warmth while ventilating the bathroom. It is especially useful in preventing the bathroom from becoming chilly after the shower and prevent water damage.
8. Bathroom exhaust fan with humidity sensor: The humidity sensor feature in the bathroom exhaust fan automatically activates when humidity levels rise, ensuring that moisture is quickly depleted to prevent mold and mildew growth in the bathroom.

What are the Sensors and their Importance in Bathroom Exhaust Fans?

The most important bathroom sensors are humidity sensor, motion sensor, temperature sensor and occupancy sensor. These sensors help to bathroom exhaust fan to operate in various conditions. 

1. Humidity sensor: The humidity sensor in the bathroom exhaust fan detects the moisture level in the bathroom and automatically activates the exhaust fan when humidity rises above a set threshold. It prevents moisture build-up and reduces mold growth and ensures the air remains refreshed and the space stays dry.
2. Motion sensor: A motion sensor in the bathroom exhaust fan activates when someone enters the bathroom. It helps to keep the bathroom air cooler and more pleasant by automatically refreshing it.
3. Temperature sensor: The temperature sensor in the bathroom exhaust fan monitors the bathroom’s temperature and can activate the fan or heater accordingly. It helps to improve the lifespan of bathroom materials by preventing them from wearing out due to extreme temperatures.
4. Occupancy sensor: The occupancy sensor in the bathroom exhaust fan detects when the bathroom is occupied and runs the exhaust fan accordingly. Its importance lies in energy efficiency, as it ensures the fan only operates when the bathroom is in use, helping to drain moisture and ventilate air without unnecessary power usage.

Are Bathroom Exhause Fans Automatic? 

Yes, many bathroom exhaust fans are designed to be automatic. Bathroom exhaust fans consist of various sensors and controls that allow them to operate without manual operation.

The advantages of an automatic bathroom exhaust fan are consistent ventilation, enhanced energy efficiency, eliminating the need for manual operation, providing better air quality, can be adjusted according to environmental conditions while maintaining a low level of energy consumption. 

Can the Bathroom Exhaust fan Damaged by the Water?

Yes, a bathroom exhaust fan can be damaged by water if it is directly in contact with it. But it does not damage with the moisture. Hence bathroom exhaust fans can handle high humidity and occasional splashes on the outer surface.

A bathroom exhaust fan can be damaged by the water from leaking pipes, excessive condensation, or direct splashes from a shower or sink. Continuous or significant water exposure can lead to rusting of metal parts, deterioration of electrical components, and potential short circuits of the bathroom exhaust fan.

To prevent damage in the bathroom exhaust fan it is important to ensure that the exhaust fan is installed properly with adequate protection against water intrusion, such as proper sealing and ventilation. 

Is a Bathroom Exhaust Fan Needed for a Waterproof Bathroom?

Yes, a bathroom exhaust fan is needed even in a waterproofed bathroom. Waterproofing protects surfaces from water damage, but it doesn’t control humidity or remove moisture from the air. An exhaust fan helps ventilate the bathroom, reducing humidity levels and preventing mold and mildew growth, and other moisture-related issues.

Read more: What to Know About Bathroom Waterproofing?

Can UV Light Kill Bathroom Mold?

Yes, UV light can kill bathroom molds. Bathroom UV light effectively penetrates into the mold spores and destroys the DNA structure of the mold. UV light consists of UV-C light with 100 to 280 nm wavelength. It effectively destroys surface mold but it takes time to destroy deeper-level mold colonies.