Do you want to find the best bathroom exhaust fan that has a humidity sensor?
Humidity sensing bath fans are a great way to automatically remove moisture, especially in homes with forgetful occupants.
In this product review, I will go over...
- My overall #1 pick for the best bathroom exhaust fan with automatic humidity sensing
- How humidity sensing bath fans actually work
- Important installation considerations
- The best features for bathroom fans with humidity sensors
Let's get started with this guide!
Top 6 Best Bathroom Exhaust Fans With Humidity Sensors
Short on time?
Below are my top picks for the highest rated bath fans with humidity sensors --- keep scrolling to learn more about these fans (and how to pick the best).
- Panasonic WhisperSense Bathroom Exhaust Fan With Humidity Sensor (My #1 Top Pick)
Delta BreezSignature Bathroom Fan With Humidity Sensor (A Close Second)
BreezGreenBuilder Bath Fan Including Auto Moisture Control (Budget Friendly Pick)
- Broan-Nutone Ultra Silent Bathroom Fan With Humidity Sensor
Our Overall #1 Rated Pick
The Panasonic WhisperSense is a great addition to any bathroom so you can automatically turn on the exhaust fan with it's built-in humidity sensor. The fan also comes with a motion sensor so you have extensive control over how the fan turns on.
The WhisperSense is very quiet at less than 0.3 sones, you will barely know that it's on. In addition, it comes with a Speed Selector switch, so you choose your fan speed at anytime --- pick between 50, 80, or 110cfm.
What is a Bathroom Exhaust Fan With a Humidity Sensor?
A bathroom exhaust fan with a humidity sensor will automatically turn on when the moisture in your bathroom reaches a certain level. The vent fan will keep running until the moisture drops to a certain level.
It is similar to how your homes thermostat works, except it is based on relative humidity rather than temperature.
The Humidity Sensor
The humidity sensor is an electrical device that responds to the moisture in the air. It is combined with a simple thermometer in order to give an accurate relative humidity reading.
With some bathroom fans, you will actually be able to adjust the relative humidity percentage as to when the fan turns on --- usually between 25% to 75%.
Again, the humidity sensor will automatically turn on the ventilation fan until the moisture level drops below the programmed level.
How Does The Wall Switch Work With A Humidity Sensing Fan?
There are three basic options in using a bath vent fan with a humidity sensors such as...
#1. No Switch
If you desire, you can actually have the humidity sensor always on so no occupant can turn it off. This may be desirable for an investment property where you don't trust the tenants or if you have small children.
#2. Independent Switch
You can also install the bath fan to have the humidity feature on a separate switch. This way you can keep a possible fan light, heat lamp, and the fan itself on separate switches. This will give you total control. Remember, if you want to add switches, you will have to add extra wiring.
#3. Same Switch
This is the most common installation in my experience. A single switch will turn on the fan and the humidity sensor. If you flip the switch once, this activates the humidity sensing mode. If you flip the switch on twice (back and forth), then this will turn the fan on manually.
What Are the Benefits of Installing a Humidity Sensing Bathroom Vent Fan?
#1. Automatic Fan Usage
These fans are perfect if you don’t want the hassle of remembering to turn it on, or if you have family members or tenants whom you think are not mindful of turning on the exhaust fan after showers.
Many people are unaware of how excess moisture can damage a bathroom and lead to poor air quality.
During my home inspections, I can clearly see how mold on grout or caulking can leave a bad impressions with buyers. When an occupant takes a shower but doesn't turn on the exhaust fan, the moisture will linger on the ceramic tiles much longer.
#2. Automatic Shutoff
How many times have we taken a shower, and accidentally left on the bath fan the whole day?
This habit not only wastes electricity but it also pushes out conditioned (heated or cooled) air to the outside. It's equivalent to having a few open windows in the home all day long.
Also, using a fan with a humidity sensor can even help prevent a fire hazard. When occupants keep a bath fan running continuously, the fan becomes more susceptible to heat buildup, and may one day literally catch on fire.
#3. Protect Your Bathroom
The other great advantage to having an automatic humidity sensing mode with a bathroom fan is that it will protect your bathroom from deterioration and mold.
Moisture is the number one enemy of bathrooms, it will literally rust the door and cabinet hardware and even any metal water lines.
If there is one place you don't want rust, it is on the water supply lines to the vanity and toilet. If the water lines leak or burst, it can cause significant damage.
I remember I did a home inspection once where half of the ceiling was removed by the seller. I asked him what happened and he told me that one of the bathroom sinks was leaking on the second level, and they were away on vacation. The total damage probably exceeded $15,000.
How To Pick The Best Bathroom Fan With a Humidity Sensor?
There are a few essential things to know when you want to choose the best bathroom exhaust fan that has a humidity sensor…
Humidity Sensor Adjustments
This is one of the main considerations with these fans. Do you want to customize that humidity level of your bathroom?
Not all exhaust fans allow you to choose the humidity setting. The fans that allow adjustment usually have a knob inside the fan housing where you can set it to 25% to 75% relative humidity.
Fixed Or Adjustable Fan Speed
With some ventilation fans, you can additionally control the fan speed as rated by CFM (cubic feet per minute of air that the fan exhausts). With the Panasonic WhisperSense, you can choose between 50, 80, or 100 CFM by using a switch inside the unit.
Most bath fans will be dual speed with a high & low speed setting. For example, in high speed mode, you may want it to run at 80 CFM, and in low speed mode, you may want the fan to operate at 6 CFM.
Make sure to check the product specs to see if this is an option for you because some fans have fixed speeds.
The bathroom size is a very important thing to consider because it will determine how “strong” of a fan that you purchase.
If you buy too strong a fan for your bathroom, you will be wasting energy as well as causing negative air pressure problems in the home, possibly impairing other home appliances such as the furnace, fireplace, water heater etc.
If you buy a fan that is too weak, then it won’t exhaust enough air and may cause bathroom moisture damage and mold growth.
Choosing Fan Strength
The fan strength is generally measured in CFM’s, or Cubic Feet per Minute. This metric will basically tell you how much air the fan can remove within one minute.
A general rule for sizing your fan is to measure the floor of your bathroom, and add 1 CFM per 1 square foot of floor space.
For example, if your bathroom floor measures as 80sf, then you would want a bathroom fan with at least a 80 CFM rating. And for bathrooms larger than 100sf, then you may want to start adding CFM’s based on how many fixtures you have in the bathroom.
The housing size is the metal or plastic container of the exhaust fan, not to be confused with the removable cover or grill which is usually larger. The housing is the bulk of the fan that will actually be screwed to your ceiling joists.
It's a good idea to measure your existing housing size before you make your purchase. You can always add wood blocking if the fan is too small in between the joists. If the fan is too large however, then you would have to cut the joists which is usually a bad idea.
It's also a smart idea to make sure you have enough vertical space you have in the ceiling cavity.
Finding A Skilled Contractor
If you want the exhaust fan professionally replaced, I always recommend Thumbtack because you can quickly get free estimates, read trusted reviews, and instantly chat with contractors about jobs.
The noise level of a ventilation fan is measured in sones which is a simple measurement of loudness.
In general, a bathroom fan that is 1.5 sones or less is considered quiet, anything below 1 sone is extremely quiet. The basic idea is that if you double the sones, you double the noise level.
Some occupants may actually want a slightly louder fan because it is a type of “white noise” and gives some privacy. Others may want a whisper quiet fan for a variety of reasons such as not waking up a child.
Where To Buy The Best Bath Vent Fan With an Included Humidity Sensor?
When selecting a vendor to buy a bathroom exhaust fan with a humidity sensor, you want to choose a company that has the largest range of products, a lot of customer reviews, great shipping options, and an excellent return policy.
Why is Amazon the Best Vendor?
On Amazon you can search exactly for the product that you want, and you can filter those products based on price, reviews, and other features.
When I purchase something on Amazon, I usually look at the top products that have the most reviews, and with the highest average review rating. Also, shipping on Amazon is usually the fastest out of all vendors, and if you are an Amazon Prime member, you frequently get free same day or two day shipping.
What Are The Best Exhaust Fans With Humidity Sensors?
Here are my best picks for bath fans with automatic humidity control including their pros and cons...
Our #1 pick for the absolute best fan, our “premium option”, is the Panasonic WhisperSense.
This bathroom fan will automatically turn on and off based on the moisture level of the bathroom. Besides this sensor, you also have the option of using an adjustable motion sensor in combination with the humidity sensor!
This fan is also very quiet at less than 0.3 sones.
You can also use the Speed Selector Switch to choose your fan speed from 50cfm, 80cfm, and 110cfm.
- It has a humidity sensor to automatically control moisture (can also be programmed with the motion sensor)
- Quiet at less than 0.3 sones
- Choose fan speed from 50cfm, 80cfm, and 110cfm using special switch
- A more expensive fan pick
- May be challenging to install and program because of enhanced functions
If you want to automatically control humidity in your bathroom, you can't go wrong with the BreezSignature by Delta.
This bathroom fan comes in an 80cfm, 110cfm, and 130cfm models (all have humidity sensors).
Using a DC z motor, this fan is quiet and made to last. Delta is one of the leading bath fan manufacturers and very reputable.
- Automatic humidity sensor includes
- 80cfm, 110cfm, or 130cfm models available (all with humidity sensors)
- DC brushless motor for a very long life
- Quality manufacturer
- Humidity sensor isn't adjustable
- Does not come with a flexible install bracket
- Made for 4" and 6" ducting
Here is our best budget friendly bathroom fan pick by Delta that comes with a built-in humidity sensor.
This fan had dual speed fan and an adjustable humidity sensor (from 50% to 80%) so you can control the moisture to your preference.
This unit is also very energy efficient at only 9.7 watts at high speed.
- Automatically remove moisture
- It is a simple vent fan, energy efficient and powerful
- Only 0.8 sones at high speed, it is extremely quiet
- It is Energy Star and HVI certified
- The fan at low speed is always on (from 0-50 CFM)
- The fan has been tested for 70,000 hours of continuous use or over 8 years — it should last a long time
- At 80 CFM and 1.3 sones, it is fairly quiet
- Extremely low energy usage at only 9.5 watts, keeps your power bill down
- Perfect for smaller sized bathrooms
- The unit may be louder than expected
- The fan may not be strong enough for your bathroom
- There may be issues with the damper
This Delta fan is also a very affordable option and it’s small size makes for an easy install.
At 70 CFM, this fan will work great for small bathrooms, and at 2 sones, it is reasonably quiet.
This fan comes with a fixed humidity sensor which is great if you don’t want to mess with programming the unit, just “set it and forget it”.
- at 70 CFM, this fan works for small bathrooms
- one of the most affordable fans on the market
- the fan is a very small size so makes for an easier install
- the humidity sensor is fixed at a set level
- at 2 sones, it may be a little loud
The Broan-Nutone bath fan is good budget friendly product that will automatically turn on using its humidity sensor.
The humidity sensor isn't adjustable, but it does come with adjustable fan timer.
It is very quiet at less than 1 sone and it is rated for 110 CFM which is sufficient for most bathrooms.
- Budget friendly bath fan with humidity sensor
- Very quiet at 0.7 sone
- 110 CFM (strong enough for most bathrooms)
- Lower quality materials
- Not made just for retrofit installation
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