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Are Humidity Sensing Bathroom Fans Worth it?

Humidity-sensing bathroom fans are one of the most critical devices in any bathroom. You might have been doing fine without them, and you are probably wondering why it is worthwhile to install one. This article aims to highlight some of the key benefits of why installing a humidity sensing bathroom fan should be your top priority.

The installation of a humidity-sensing bathroom fan will undoubtedly cost you quite a sum. Usually, humidity-controlled bath fans cost about twice as much as their regular counterparts.

This leaves may leave you wondering whether such an investment is worthwhile. The truth is that installing a humidity-sensing bathroom fan is worth every penny, and it will lead to many benefits, as you will discover from this article.

Read on to learn why a humidity-sensing bathroom fan is superior to its manual counterpart. Later I will let you on a secret how you could get the same functionality with a fraction of the cost.

Humidity sensing bathroom fans are worth it because they automatically control bathroom humidity. Most people turn off the bathroom fan too soon after taking a shower. Over time this will lead to moisture damage. They are especially useful in rentals, as they ensure that the fan is started even when the residents forget to turn it on.

Humidity Sensing Exhaust Fan Will Prevent Moisture Damage

Keeping the moisture levels in your bathroom in check is one of the most important uses of a humidity-sensing bathroom fan. This is because moisture has a load of negative impacts, especially on your bathroom. Some of the effects of excess moisture that the humidity-sensing bathroom fans will aid you in overcoming include the following:

Prevent peeling of paint

Keeping your bathroom walls in top condition is very important. You may have seen peeling paint and wondered why this happens and what could be done to prevent it. Paint starts to peel when the humidity of the room is too high for extended periods. For example when the bathroom fan is not used. The high humidity causes water to condense on the walls. If the exhaust fan is not turned on, the water could remain on the walls for hours.

This is where a moisture sensing bathroom fan comes in handy. Since it will automatically turn on when the moisture levels rise above a set point there is no chance for peeling paint because the water will dry before it could damage the paint.

Prevent warping of the door

The last thing you’d wish is to have your bathroom door warped, as this would mean that there is no privacy. Unfortunately, if you do not have a moisture sensing bathroom fan, you cannot run away from this challenge. Moisture is destructive, especially on wooden doors, and this is why you should install a humidity control system to prevent warping. 

Prevent growth of mold

Mold likes to grow in damp environments, which makes your bathroom the ideal breeding ground for these fungi. The problem with mold is that it causes discoloration of the walls and floor. It is also challenging to eliminate once it has grown in your bathroom. Some surfaces will be stained by mold so badly that they can not be cleaned.

A bathroom fan with a humidistat will automatically keep the humidity levels so low that it is impossible for the mold to grow.

Prevent bad odors

The excess moisture in the bathroom will, without a doubt, lead to the development of a foul odor. This may spread to other areas in the house, and you definitely would not want such a scenario. It is effortless to contain as you only need to install a humidity sensing bathroom fan, and all the odor will be wafted away via the exhaust vent. 

Set and Forget

Think about some mornings when you wake up late, and you have to take a quick shower, or else you will be late for work. Admittedly, on such days, you have little concern as to whether you switch the bathroom fan on or not. 

Also, forgetting to switch on the bathroom fan even on a normal day is a common occurrence that can happen with anyone. Overtime not exhausting the moist air out of the home will lead to expensive moisture damage.

This can be easily avoided by installing a humidity-sensing bathroom fan. The logic behind it is quite simple. All you need is to set it up, and it will automatically switch on when there is excess moisture and turn off when the humidity drops back down.

With a humidity controlled fan or a switch you can think about more important things. Install it once and you never have to think about turning on the fan again.

Humidity-Controlled Fan Will Save Energy

Saving on electricity costs will help keep your expenses low. Switching off any device that is not in use is very important in enabling this. For the manual bathroom fans, one has to switch it off after about 30-60 minutes after taking a shower.

Imagine leaving the bathroom fan on in the morning and having it running all day because you forgot to turn it off when leaving for work.

Since bathroom fans don’t use all that much electricity, the largest cost is going to be the heating/cooling cost because you can lose excess heat or cold air through your bathroom fan.

Since bathroom fan exhaust air out of the house, energy will be wasted when the fan runs for too long. Imagine the fan blowing warm air out of the house for the entire day. This is a lot of heat energy wasted.

Cheaper in the Long Run

As highlighted above, the humidity sensing bathroom fans’ ability to turn off the fan at the right time will help keep the energy costs down.

However, this is not the only way through which installing this device will assist you in cost-cutting. Consider how expensive it is to repaint your bathroom walls that are stained from mold. If the manual fan has been not turned on for years, the moisture damage in the attic could end up costing thousands.

Bath Fans With a Humidistat Are Perfect for Kids’ Bathrooms

Small children often forget to turn on the bathroom fan before jumping into the shower. By installing a fan with a humidity sensor or a humidity-controlled switch you can be sure that the fan is running when there is excess moisture in the room.

This will improve your relationship with the kids’ by avoiding many arguments about why they always forget to turn the fan on.

Another solution could be to use a timer switch that is wired so that it will turn on with the bathroom light. The problem with this solution is that every time the light is turned on the fan will run for 30-60 minutes. This will waste a lot of energy over the long run. This is why I always recommend a humidity-controlled fan/switch.

Humidity-Controlled Bathroom Fans Are Essential in Rental Properties

If you run a rental property, the humidity control bathroom fans are very important. Tenants often forget to switch on the bathroom fan after having a shower. They will only start complaining when the paint on the walls starts to peel or visible mold can be spotted on the walls or ceiling.

Installing a humidity-controlled bathroom fan in a rental property will come in handy in overcoming this problem. 

First, the automatic bathroom fan will serve the tenants well as they won’t have to keep worrying about turning on the fan. This will improve the air quality.

Also, it will be significant in saving on costs. The aim of rental properties is to maximize rent collections by minimizing the expenditure. These fans will be vital in enabling increased profitability. 

How to Find the Best Humidity-Controlled Bathroom Fan

Bathroom exhaust fan airflow CFM chart

I won’t recommend any specific fan here. I could, but it would not be helpful since not all bathrooms call for the same bath fan.

Here are some of the factors that must be taken into accont:

  • Duct size
  • Capacity (CFM)
  • Noise level
  • Cutout dimensions

I have a detailed article that will help you choose the perfect bathroom fan for you. Don’t worry it is not difficult. Just follow the 6 easy steps and you will have yourself a perfect bath fan in no time!

Consider a Humidity Controlled Switch Instead

You might already have a manually operated bathroom fan, and you feel that replacing it is unnecessary.

Do not worry about that, I have a solution!

You can consider buying a humidity-controlled switch and connecting this to your fan. This will automatically convert it into a humidity-sensing bathroom fan. 

TOPGREENER Dual Tech Humidity Sensor Switch, Infrared PIR Motion & Air Moisture Detection, Bathroom Fan & Light Control, Adjustable Timing, NEUTRAL WIRE REQUIRED, UL Listed, TDHOS5, White

There are a plethora of such switches in the market. Nonetheless, none will serve you better than the TOPGREENER Dual-Tech Humidity Sensor Switch(amazon link). This switch will combine both the bathroom fan and light in one.

If you are brave enough to install it yourself, here is the wiring diagram.

TOPGREENER Dual Tech Humidity Sensor Switch, Infrared PIR Motion & Air Moisture Detection, Bathroom Fan & Light Control, Adjustable Timing, NEUTRAL WIRE REQUIRED, UL Listed, TDHOS5, White

Avoid Buying a Cheap Humidity Sensing Bathroom Fan

You have probably heard of the saying that cheap is expensive. This is very applicable for humidity-sensing bathroom fans.

Cheap humidity-controlled bathroom fans use low-quality sensors. Most will barely last a year. This is why it is important to choose a quality brand.

The most common problem with them is that they will cause the fan to turn on by itself even if there is no excess humidity.

This is likely caused by an incorrect signal from the defective humidity sensor

How Do Humidity Sensing Bathroom Fans Work?

Having known the upsides of having a humidity-sensing bathroom switch, the next thing is understanding how it functions. The principle behind the operation is quite simple. The device has a humidity sensor that registers a change in the moisture content in the bathroom. This prompts the fan to start, and it wafts all the moisture away into the exhaust vent. 

The device also automatically detects when the moisture has been reduced. When this point is reached, the fan turns off. The process is repeated every time there is an increase in moisture.

What Humidity Should My Bathroom Fan Be Set At?

The recommended setting for a humidity-controlled bathroom fan should be approximately 60%. Setting your humidity sensing bathroom fan at the right humidity is important because the device operates within the set limits.

Unfortunately everybody can’t set the fan at the same level since local climate will affect the normal moisture level.

This is why it is best to experiment with different settings. 60% is a good place to start. If the fan is constantly running, raise the “turn on humidity level” and if the fan won’t turn on after a couple of minutes of showering lower it a little bit.

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