new bathroom tub, tile surround with niche, and toilet

Kendall "aka Renos"

Founder, Lead Instructor of Renos 4 Pros and Joes and Bathroom Update Guide

Why Bath Fans are a Good Idea

If you have an older home, there is a good chance that you have at least one bathroom that doesn’t have a bathroom exhaust fan. Exhaust fans help solve several problems that are common and unique to bathroom spaces. Whether your bathroom is having issues or you are planning a remodel, a bathroom fan is a thoughtful improvement for an existing bathroom, or as part of the design of a new or remodeled bathroom.


So, if you are asking yourself “Should I install a bathroom exhaust fan?”  the short answer is YES. You should install a bath exhaust fan because if used properly, it can prolong the life and condition of your bathroom space by removing trapped moisture and humidity which can over time damage nearly every building component in the bathroom. Keep reading as we dig a little deeper into the benefits of a bath fan as well as some of the scenarios where not having one can become an issue.  

Bathroom Odors

We all know that the two of the main purposes for a bathroom are to do “Number 1” and Number 2.” The vent fan will help keep what goes on in the bathroom from easily exiting the space and spreading throughout the property. Your housemates and guests will greatly appreciate the fan.


Bathroom Sounds

The two bathroom activities mentioned in the previous section also create sounds. Most bathroom fans are loud enough to mask or cover some of these noises. This provides an added layer of privacy for the person using the bathroom. This is especially helpful when a bathroom is located in a high traffic area. I’ve been inside homes where the only bathroom on the main level of the home is literally located inside the kitchen of the home.

Awkward Bathroom Moments

Can you imagine being a guest at a dinner party and while everyone is congregating in the kitchen after dinner you have to excuse yourself to a restroom that is still in the kitchen? Where only the bathroom door separates you from being in the middle of the party?! OMG. I’ve seen this play out in real life and it can be really awkward. And while relocating the bathroom may be an option for some, the cost may be too high to make it worth it for others. But adding a bathroom fan is a lower cost alternative that can definitely help mask those sounds and vent the odors out of the house(instead of into the kitchen)!



Taking showers and baths creates humidity. And hot water makes even more humidity. Many of the building components used to build your bathroom do not stand up well to humidity and moisture over a long period of time.


Bathroom Mirrors Show Signs of High Humidity

Probably the first place you will see signs of moisture will be on the bathroom mirror. You may notice that the mirror is slightly hazy, or in moe extreme scenarios, the mirror is completely fogged over to the point where you cannot clearly see your reflection. This is a sign of excessive humidity and its also not good for your mirror, but it can be even worse for your walls and ceilings.


Bathroom Ceilings

Your bathroom ceilings may be one of the first locations where you notice serious issues begin to form. Heat rises, and if your bathroom does not have an exhaust fan the hot wet air has nowhere to escape. This often results in condensation forming on the ceiling. This is bad for your drywall or plaster ceilings.  


Bathroom Walls

As you could probably guess, the next location where you will likely see signs of moisture issues are the walls. The trapped moisture basically coats everything in the immediate area including the walls.

The ceilings and walls are two of the most vulnerable surfaces because they are usually made from softer more porous materials that more easily absorb moisture.


Signs of Moisture in the Bathroom

Over time you may notice that the paint on the ceilings and walls begins to crack and peel. You also may notice that the drywall taped joints begin to show on the ceilings and walls. Over time you may also see the drywall mud begin to crumble and come out of the joint.

In a more extreme scenario, you may begin to see black, green or brown spots start to form on walls and ceilings. These are signs of microbial growth, and you will want to get this under control as soon as possible.


No Bath Fans on Home Inspections

If you are in the process of selling your home you may now be concerned that not having a bath exhaust fan will come up on your home inspection. This is a valid concern. And how big of a deal it is will depend on a few factors. One factor will be the age of the house.

If the home was built before bath fans were commonly used, and the bathrooms have not had significant improvements made to them, you may be ok. Conversely, if you’re home was built or remodeled since bathroom vent fans have been required, you may have more of an issue. Someone likely should have caught that during construction or during the remodel (especially if a permit was pulled).  


Another factor is what is common for the area where the home is located. If no houses in the region have bath fans, then the inspector may note that there is no fan to inform the client, not necessary to say that its a red flag item. Look at your inspection report closely and don’t be afraid to ask your home inspector some follow-up questions.


Bath Exhaust Fan Not Vented Outside

Now, this is a very common issue in my neck of the woods. It’s common for both kitchen and bathroom vent fans that were installed “back in the day.” That was before my time, but it seems like must have been the norm to just vent the fan into the attic space and leave it that way.

However, times have changed and we now know that blowing hot moist air and humidity into the attic is not good for the house. If you already have a fan in place, you may be able to install ducting to the existing fan and vent it without having to replace the fan. Make sure that the existing fan is in good working condition before you take the time and effort to run duct and vent it to the exterior.


Windows in Bathroom for Ventilation

In some jurisdictions, a functioning window in a bathroom eliminates the mandatory requirement for a bath exhaust fan. You will need to check your local building code to determine the requirements in your area.


Even bathrooms with windows commonly have bath fans for their convenience. And larger bathrooms that have a separate room for the lavatory often have a separate fan in each area of the bathroom.

Alternatives to Adding a Bath Fan

Leave the Bathroom Door Open

While its not an ideal solution, you can leave your bathroom door open, which will allow the trapped moist air to escape the bathroom, and potentially alleviate some of the wear and tear on your bathroom. But on the flip side, the moisture and humidity aren’t good for any part of your house, and opening the door is spreading the root cause to other areas.

I’m not presenting this as a solution, but rather an option to help your bathroom if you are not planning to add a fan in the immediate future.


If you have a window in your bathroom, then, by all means, use it. If the window painted shut or for some reason doesn’t open, you should look into what it would take to make it functional again for the sake of preserving your bathroom.


Taking Shorter Showers

I have another option that you aren’t going to like: Take shorter showers. It goes without saying that you will not create as much humidity if you don’t introduce as much hot moisture into the space. Another unpopular option is to turn down the thermostat on the water heater and take cooler showers.

I have some personal experience with this one. I lived in a home for several years that didn’t have a bath fan and never had an issue. But one day I decided to turn up the thermostat on the water heater so I could increase the temperature of the water at the kitchen sink and the shower. It literally took less than 6 months for me to start to notice visible changes on the ceilings and walls in the bathroom. The only thing that changed was the temperature of the water.  


If the budget will allow for it, a bathroom fan gives you an excellent way to remove odors and moisture from the bathroom. Even if you don’t run the fan all the time, the vent opening in the ceiling and the duct still provides a path for odors and moisture to escape from the bathroom.

Consult a Pro Before Taking Any Major Steps

Before you begin, make sure to consult the appropriate contractors and professionals to ensure that you fully understand what’s involved with adding a bath fan to your specific property. There may be conditions that are unique to your home, and an in-person inspection is advisable to identify these considerations and cost in order to help you make a fully informed decision.