5 Bath Fan Installation Mistakes to Avoid

Reading time: 4 minutes

Safety

Which of these installation gaffes do you recognize?

Foggy mirrors

Mold and mildew

Noisy operation


Image a white airy bathroom with a bathtub and an open balcony and lots of trees

Contractors know too well that many things can go wrong with a bathroom’s ventilation system, causing costly callbacks and distrust among homeowners.

However, few realize that these common bathroom fan failures are often the result of faulty installation – not a poor bathroom fan.

Pros can reduce callbacks and strengthen their reputation by keeping an eye out for these common installation mistakes.

Common Bath Installation Mistakes

1. Opting for the Minimum

Often, contractors select a bath fan solely based on the CFM required to ventilate the space without considering other performance factors. Although basic ceiling mount bathroom exhaust fan will meet the minimum code requirements, they often fall short of homeowner’s expectations.

Builders and contractors can install Remote Mount Bathroom Fans to keep up with increasing demand for quiet, hassle-free ventilation. The bath fan motor is mounted in a remote location away from the ventilation grille to eliminate noise. These fans can also be used to ventilate two bathrooms with one fan, eliminating the need for two bath fans.


2. Selecting the Wrong Size

Most contractors think that selecting a bathroom fan that is too small for the CFM requirements is the only sizing issue they can make. However, oversizing can be just as detrimental because it can create an imbalance by pulling out too much air. This deficit causes unfiltered outside air to be pulled into the space through leaks and cracks.

Calculations for one bath fan

According to the guidelines of the Home Ventilating Institute (HVI), baths that are 100 square feet or smaller require 1 cfm per square foot of bathroom or a minimum of 50 cfm of fresh airflow. To find the square footage simply multiply the length of the bath by the width.

This math changes slightly when working in luxury bathrooms that include features like jetted tubs. A standard tub, shower, or toilet requires 50 cfm. By contrast, a whirlpool, garden, or jetted tub requires 100 cfm.

Calculations of two bathrooms

Another unique example is using a remote bath fan to ventilate two bathrooms with one fan. In these instances, simply add the airflow requirement of the two bathrooms together. 


3. Placing the Fan in the Wrong Location

Do you typically place the bathroom fan in the center of the room? Although this is a very common practice, it is actually the culprit behind those pesky foggy mirrors and moisture buildup. 

When the fan is in the center of the bathroom, it actually drags the moisture from the shower across the room rather than venting it straight out and away. To prevent this, bathroom fans should be placed in the shower or just outside of the shower to eliminate moisture at the source.

Keep in mind that the primary purpose of a bathroom ventilation system is to remove moisture from the air. While bathroom fans also offer a solution to eliminate odors and ensure fresh air, the design and placement should always support the fan’s primary purpose.


4) Driving Up Energy Costs with Multiple Fans

Large, luxury bathrooms. Water closets. Home spas with jet tubs. These bathroom applications often require several ventilation points, causing contractors to install multiple fans to meet airflow requirements.  

While multiple fans can do the job, they often drive up energy costs and create excessive noise when operating simultaneously. Rather than install and operate two bathroom fans, a Remotely Located Bathroom Fan can be used to vent two exhaust points using one fan. Not only is this a more cost-effective solution, it’s less noisy. 

Have more questions about proper bath fan installation? Get answers to all of your bathroom ventilation questions in our FAQs.

Find Premium Bathroom Ventilation Solutions

It takes more than proper installation to provide effective bathroom ventilation. Selecting the right bath fan for your specific application is the first step to providing effective bathroom ventilation.

Find your perfect solution! Use the Bathroom Fan Selection Tool and Find a Dealer near you.