Bathroom Dehumidifier Vs Exhaust Fan: Which One Is Better For You?

Liz Yang

People often use a bathroom dehumidifier or an exhaust fan to combat the dampness in the bathroom. While both of them can remove excess moisture from your restroom, which one suits you better.

If your bathroom is humid all day long, using a dehumidifier is a better choice. Otherwise, installing an exhaust fan is adequate to get rid of clammy air there.

However, this is just one of the deciding factors. Bathroom dehumidifiers and exhaust fans have a set of pros and cons which can affect your choice.

In this post, I’ll make a list of them and carefully compare them to help you decide which one is best for you.

Difference between bathroom dehumidifiers and exhaust fans

Even though the primary function of bathroom dehumidifiers and exhaust fans are similar, they work on different principles. 

Dehumidifiers remove moisture from the air by converting it to liquid water. When air is drawn into the machine, it passes through a cold coil that condenses the moisture into water, and the drier air is reheated by the condenser coil before being returned to the room. This is how a compressor dehumidifier works. 

If you have a desiccant dehumidifier, rather than going through two coils, it will pass through a wheel which will absorb the moisture. 

Regardless of the type of dehumidifier, you have to drain the water from the water vapor in the air. 

Unlike the bathroom dehumidifier, the bathroom exhaust fan doesn’t collect any water. When the motor kicks in, the blades will spin rapidly and pull the moisture out of the space. Bathroom fans are not portable. You should install it on the ceiling or window. 

You see, they work in different ways. Accordingly, they will accommodate different needs and have various pros and cons. (More on that later)

Benefits of bathroom dehumidifier 

bathroom dehumidifier

Bathroom dehumidifiers can remove the humidity persistently

The bathroom is always the wettest place in the house due to your daily activities and that it is close to the water source. 

A dehumidifier can remove moisture continuously, keeping the bathroom dry all day. No matter how humid your room is, there is always a model that can handle it. Since most bathrooms are small, a mini dehumidifier is sufficient in most cases. 

We can’t, however, run an exhaust fan all day. It will easily overheat and malfunction.

Bathroom dehumidifiers can keep the humidity level under control

Most dehumidifiers now include a built-in humidistat, which means the machine will turn on and off when the humidity reaches a certain level. This keeps the bathroom comfortable without being overly humid or dry.

Exhaust fans do not have this type of sensor. It will not turn on automatically if there is excessive moisture in the bathroom.

Easy to set up 

Setting up a dehumidifier is easy peasy! Just move it to the bathroom, plug it in, press some buttons, and you are all set. You don’t need to attach it to anything, and everybody can get it done.

Installing an exhaust fan could be more complicated and should be done by an electrician. 


Drawbacks of bathroom dehumidifier 

Higher electricity consumption 

The average wattage of a dehumidifier is about 400W, and a mini model is only about 22.5W, which is not high.

Exhaust fans use even less electricity than bathroom dehumidifiers, with wattages ranging from 5W to 40W.

Furthermore, you may need to run a dehumidifier in the bathroom for a few hours or all day, which will result in much higher electricity bills. Choosing an energy star-certified model can save you up to 15% on your energy bill.

Take up more spaces

Again, bathrooms usually have limited spaces. Putting a dehumidifier inside it may interrupt your walk path or take up the area where you want to store your skincare products. 

A dehumidifier is a good choice, but it may not be an applicable option. 

You may need to dump the water frequently

Every bathroom dehumidifier has a water reservoir to collect water. If your bathroom is too humid, you may need to empty the bucket a few times a day, which is tedious. 

Some models have a drain port, allowing you to direct the water to the floor drain or a sink.  In some cases, a pump is required to ensure that the water flows smoothly.

Higher product price

In general, a medium-sized bathroom dehumidifier costs more than an exhaust fan. However, if you have a small bathroom, you can choose a mini model, which may cost less than a bathroom fan.

Benefits of exhaust fan 

bathroom exhaust fan

Exhaust fans can pull out moisture in a short time

A dehumidifier can constantly remove the moisture, but it will take a few hours or even a day to work.

The exhaust fan is more efficient at removing moisture and steam from your bathroom. If you turn on the fan while showering, you can turn it off before leaving because most of the water has been removed.

It keeps water vapor from condensing on the shower wall, lowering the likelihood of mold growth.

Exhaust fans can remove odor 

Compared to a bathroom dehumidifier, an exhaust fan has more functionalities. It can remove not only the humidity but also the fume or other smells. 

It can effectively eliminate the odors after doing your business, causing much less embarrassment. Assuming someone is waiting to use the bathroom next to you, an exhaust fan could make their experience much better.

Beyond that, the added air circulation can bring in more fresh air, improving the indoor air quality. 

Exhaust fans can remove heat

After taking a hot shower, your bathroom can become very hot. It could be annoying in summer times. Running a bathroom fan can pull the heat out of the room. 

A dehumidifier can make the room feel cold to some extent by lowering the humidity level. However, it will blow hot air, gradually raising the temperature. In a warmer climate, using a bathroom dehumidifier may not be a good idea.

Exhaust fans can be cheaper 

Because of the simple mechanism, exhaust fans don’t have a high price tag. You can get a pretty good one for under $100, which is less than the price of a standard dehumidifier.

Besides, installing a window fan is straightforward. By sliding the bathroom window up, you are able to secure it between the window and window frames. Installing a ceiling fan can be complicated, which I will cover later. 

Exhaust fans are space-saving

When running a dehumidifier, you must place it on the floor or on the table, which will take up the valuable space in your bathroom.

Exhaust fans could be better for a tight space because they will be installed on the window or ceiling, which will not occupy the space at all. 

Drawbacks of exhaust fan

Exhaust fans can’t really control the humidity level

Regarding humidity control, exhaust fans can send the steam and humid air out of the house. However, they can’t maintain it or control it under a certain level. 

Again, it doesn’t have a sensor to do it. In addition, when they pull out the air,  they will create a negative pressure in your home, which facilitates the outside air creeping into the bathroom through cracks and crevices. 

As a result, the indoor air will always mix with the outdoor air, making the humidity level lose control. The air outside can become very humid at times, increasing the moisture level in your home.

Window fans allow insects and bugs to come in

While window fans are affordable, they have their shortnesses. Firstly, they make the bathroom windows useless. You can’t open the window without removing it. 

Secondly, the insects and bugs can get into the bathroom through the crevices between the blades. The bathroom is usually humid, and bugs like to stay in wet places. 

Installing a ceiling fan is difficult and expensive 

You don’t need to pay labor costs when setting up a bathroom dehumidifier or a windows fan. However, hiring a pro to install the ceiling fan is a necessity unless you have the expertise. 

To get it installed, you need to cut the ceiling and connect the fan to the power source, which can involve many steps. Accordingly, the labor cost may be higher than you expect. 

Which one should you pick?

Until now, we have compared bathroom humidifiers with exhaust fans from many aspects.

A bathroom dehumidifier can control the humidity level precisely and constantly, whereas an exhaust fan can expel a large amount of moisture out of the house in a short time. 

A bathroom dehumidifier may be preferable if you live in a humid area since it can keep the bathroom dry all day. Otherwise, an exhaust fan could be a better choice since it is space-saving and can remove the odors and heat at the same time.  

Liz Yang is the founder of Airsmartly. She has been working at home for a few years and realizes that the performance of the HVAC system plays such an important role in our life. She has tested a lot of products in person, like humidifiers, air purifiers, dehumidifiers, and ACs, and wants to share tips about using or troubleshooting these products with you. Her uncle is an HVAC expert with over 30 years of experience in the field, and often offers assistance when she is unsure how to handle a situation. He is also in charge of reviewing the articles on this site.

Leave a Comment