Want to find the best bathroom exhaust fan that has a humidity sensor?
You are in the right place.
In this special guide from Home Inspector Secrets, you will learn…
- The benefits of buying a fan with an automatic humidity sensor to control the fan
- The pros and cons of our top rated bathroom exhaust fans
Let’s get started with this guide!
Our Top 5 Best Bathroom Exhaust Fans With Humidity Sensors
Our Overall #1 Rated Pick
(Updated as of 9/5/2019)
- Automatic control of bathroom humidity
- Also includes a motion sensor (no wall switch required)
- Various options to control fan with motion and humidity sensors together
- Very quiet at less than .03 sones
- 80 CFM rating
- High quality build from Panasonic
My overall top pick for bathroom exhaust fans with humidity sensors is the PANASONIC WHISPERSENSE with dual motion and humidity controls. With this premium bathroom exhaust fan, you can automatically remove the moisture in your bathroom while you barely even here it running. The options to control moisture are great, and you can program it how you want.
What is a Bathroom Exhaust Fan With a Humidity Sensor?
A bathroom exhaust fan with a humidity sensor automatically controls the moisture level of your bathroom. 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 experts such as GreenHomeGuide.org agree that to have the most efficient bathroom exhaust fan, you will need to control your fan based on the actual humidity level of your bathroom — and not just by guessing.
How many times have we taken a shower, and accidentally left on the fan the whole day? This habit can waste a lot energy by using electricity and by expelling conditioned air to the outside. Also, if we forget to use a bath fan, it can leave our bathrooms vulnerable to mold and drywall damage.
According to the Colorado Springs city government, 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 (especially if never cleaned), and may literally catch on fire.
The Humidity Sensor
The humidity sensor is an electrical switch that checks the moisture level of the air. As a result, it automatically turns on the fan until the moisture drop backs below the programmed level.
For example, if the set level of humidity is 50%, then once the humidity exceeds 50%, the fan will turn on until it drops back below 50%. It works the same way as your central thermostat; except it controls for moisture, and not temperature.
There are a wide range of options for bathroom exhaust fans with humidity sensors. With some fans, you can control the actual humidity level where the fan automatically turns on. And yet with other fans, it is a factory set level that is not changeable.
The Wall Switch
Pretty much all fans with humidity sensors can be wired to a wall switch which gives you some manual control over the humidity sensor. When you flip the wall switch just once, the fan goes into auto sensing mode. In this mode, the fan will turn on and off automatically based on the preset humidity level.
But what if you want the fan to turn on right now, rather than waiting for the humidity to rise? All you have to do is flip the wall switch on and off twice, and the fan will turn on instantly.
It is up to you whether you want to wire it to a wall switch. The negative side of having a wall switch is that some users may accidentally shut it off and not use the fan. If you simply do not trust the bathroom user to properly use the fan, then your best bet is to have an automatic humidity sensor without a wall switch.
It's important to know that to use all of the features of the exhaust fan through a single wall switch, you may need entirely new wiring such as 14/3 wiring --- this has 4 wires --- 1 ground, 1 neutral, two hot (red & black).
Fixed Or Adjustable Fan Speed
With some fans, you can additionally control the fan speed as rated by CFM (cubic feet per minute of air that the fan exhausts). Most bath fans will be dual speed with a high & low speed setting just like whole house fans. 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.
A humidity sensor as part of a bathroom fan is a very useful feature to make sure that people actually use the fan — without having to think about it. If you have children, tenants, or other individuals whom you think may not understand the importance of always using a bathroom exhaust fan — then a humidity sensor is ideal.
According to HVI.org, uncontrolled bathroom humidity can lead to mold, mildew, and even structural damage to your home. Having a high quality bathroom fan is even more important in modern homes because they have a lot of insulation and are almost totally air tight.
The many advantages of having a bathroom exhaust fan with a humidity sensor are…
- Prevent bubbling and peeling paint
- Stop mold and mildew growth on drywall and caulking
- Protect your metal and cabinet hardware from rusting
- Improve the air quality throughout your whole home (not just the bathroom)
- Automatically reduce bad smells
- Guarantee that the exhaust fan will actually be used
How To Pick The Best Bathroom Exhaust 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…
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.
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. Most fans will come between 60CFM and up to 130CFM.
According to the Home Ventilating Institute, 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 is usually preferable to purchase a fan that will fit into the hole of the fan that you are replacing — it makes for a much easier installation.
Either way, it is important to measure your existing housing size before you make your purchase unless it is a new install. And even with a new install (not a replacement) you may still want to know how much horizontal space you have in between your ceiling joists, as well as how much vertical space you have in the ceiling cavity.
Removing the existing bathroom fan cover is usually a very simple job. Just pull on the cover, and push in the two metal clips to unlock the cover or grill.
The noise level of a bathroom 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.
How is a Bathroom Exhaust Fan With a Humidity Sensor Different From Other Bathroom Fans?
A bathroom exhaust fan with a humidity sensor has a few key differences with other bathroom exhaust fans such as:
- Ability to control moisture automatically based on actual humidity
- Without a humidity sensor, other fans have to use a timer switch to turn off
- Some bathroom fans have an LED light as part of the unit
- There are exhaust fans ]have heaters that will instantly warm up the bathroom (here is our best picks for fans with heaters)
- A few bathroom fans even have all three features in one (a heater, light, and humidity sensor)
Where To Buy The Best Bathroom Exhaust Fan With an Included Humidity Sensor?
When selecting a vendor to buy a bathroom exhaust fan with a heater, 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. At Home Inspector Secrets, we highly recommend buying from Amazon because it is a seller that you can trust.
Why is Amazon the Best Vendor?
On Amazon you can search exactly for the product that you want, and you can filter that 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 two day shipping.
The return policy of Amazon is very easy with a 30 day return window for all items. If the fan is sold by a third party seller on Amazon, make sure to read their return policy on the product page because it may slightly differ.
What Are The Best Exhaust Fans With Humidity Sensors? (**2019 Review)
Here is our best budget friendly bathroom fan pick 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.
- It is a simple fan, energy efficient and powerful
- Only 0.8 sones at high speed, it is extremely quiet
- It is Energy Star and HVI certified
- Many positive Amazon reviews
- The fan at low speed is always on (from 0-50 CFM)
Our higher quality pick for a powerful fan in larger bathrooms is the Delta BreezSignature.
This fan is a dual speed unit with a fixed humidity sensor that offers a no fuss option.
This intelligent fan will first go to high-speed, then low speed, and then will shut off completely — all on autopilot!
At 130 CFM and only 2 sones, this is a very quiet fan at this level of power.
- An intelligent fan with different speeds and auto shutoff
- A powerful exhaust fan for larger bathrooms
- Very quiet for a 130 CFM fan
- It has a fixed humidity sensor of 60% moisture so you can’t change it
Our second favorite pick for most affordable is the BreezIntegrity.
This fan is great for smaller bathrooms where you don’t want an energy hog.
Rated at 1.3 sones at it’s highest speed, this fan is very quiet.
- 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
Our pick for the absolute best fan, our “premium option”, is the Panasonic WhisperSense.
This bad boy is for larger bathrooms and is rated at 110 CFM.
With only 0.3 sones, this is the quietest of most bathroom fans on the market.
Not only does this fan have an adjustable humidity sensor (from 30% to 80%), but this fan also has a motion sensor and a timer delay.
There are so many control options with this fan that it will make your head spin.
- The fan comes with a motion sensor that can detect movement in your bathroom and automatically turn on the fan
- It has a humidity sensor to automatically control moisture but it can also be programmed with the motion sensor and timer
- The humidity sensor has the widest control range, all the way from 30% to 80% humidity
- Due to it’s advanced technology, the fan may not be user friendly without reading the manual
- The most expensive fan out of our picks
- Fan will likely be the most difficult fan to install and program
The Panasonic WhisperSense is our #1 best pick in 2019 because of the following reasons…
- This fan comes with a motion sensor, humidity sensor, and timer so you can combine these features to have absolute control over your fan
- The WhisperSense gives you the most control over bathroom humidity over all the other fans — all the way from 30% to 80% humidity
- At 110 CFM, this powerful bathroom fan is great for larger bathrooms but is still energy efficient
- At a remarkable 0.3 sones, this powerful fan is also extremely quiet, which is why it is called “WhisperSense”
No Switch Required
- Due to it’s wide range of auto control options, a wall switch is unnecessary which will save money on the installation