Why Is Water Dripping From Bathroom Exhaust Fan?

Exhaust fans keep your bathrooms moisture-free and smelling fresh. However, they also have their fair share of issues. If you have a bathroom with an exhaust fan, you may experience water dripping from the fan on occasion, and it can be a little bit alarming to see water coming from seemingly nowhere. The good news is that knowing why it happens can help you to fix it before it creates any substantial problems for the house or the residents. 

Condensation is the main cause of water dripping from bathroom exhaust fans. This water condensation can happen due to improper insulation on the exhaust pipe. The other reasons for condensation can be a clogged vent, dirty exhaust fan, melting ice on the roof, or incorrect installation of the exhaust fan.

Let’s see in detail what causes water to drip from your bathroom exhaust fan and how to fix it, so it won’t cause you any major problems related to water damage.

Water dripping from bathroom exhaust fan

Reasons why water drips from a bathroom exhaust fan

If you’ve ever experienced water dripping from your bathroom exhaust fan, you’re probably wondering why it happens and how to prevent it from happening again. Water leakage can cause mold and related problems for your house structure. Finding the reason for this dripping will help you look for a solution to avoid it in the future and keep your washroom dry and comfortable. 

Take a look at this list of top five reasons why water drips from your bathroom exhaust fan below:

1. Lack of insulation on the exhaust pipe

In winters, most people notice water dripping from the exhaust fan right after a hot shower. While many don’t pay attention to it, some homeowners want to know the reason for this strange phenomenon before it damages their property. 

This water dripping is caused by condensation in the exhaust hose. Due to the lack of insulation on the exhaust duct, when the warm and moist air from the bathroom combines with the cold air in the attic or outside the house, it turns into water droplets inside the duct. This water or condensation trickles back down the exhaust fan and drips in the bathroom. 

Condensation can also happen during summer when humid air in the exhaust duct gets cooled down by the air conditioning. When you shower, the humid bathroom increases the moisture level in the duct, causing the water to drip back into the bathroom through the exhaust fan.

2. Vent blockage 

If you notice that your bathroom is still humid and foggy even after turning on the exhaust fan and water drips from it, there is a chance your exhaust vent has some blockage. If humid air is not thrown outside, it can quickly result in condensation and water dripping through the exhaust. Before finding a solution to this problem, you need to determine if your vent is blocked. 

Check if stale air is moving out of your vent by doing a tissue paper test. Turn on the exhaust fan, make a folded sheet of toilet paper and bring it close to the exhaust vent. If it sticks to your exhaust fan vent, it means that your fan is working fine, and there isn’t any blockage. But if your exhaust fan doesn’t suck up the tissue paper, it means your exhaust vent is clogged and needs to be cleaned.

3. Dirty bathroom exhaust fan

If your bathroom fan is dirty, it can’t do its job of exhausting hot, humid air. Bathroom exhaust fans have a grill in front with holes or slots. Over time, these holes and slots accumulate dust in the form of lint, preventing the exhaust fan from working efficiently. 

A dirty exhaust fan causes condensation in the vent, just like any blockage in the vent does. A hindrance in airflow towards the outside may result in water dripping from the exhaust fan. Moreover, this lint formation also poses a fire hazard, so it should be dealt with immediately.

4. Water from the roof

There can be two reasons for water from the roof finding its way down to the bathroom exhaust fan and leaking into the bathroom. It could be rainwater of melted ice or snow responsible for a leaky exhaust fan. 

A defective vent cover or an improperly installed vent cover can leak water through the exhaust fan when it rains. The roof’s slope can facilitate the rainwater to enter through a cracked or open vent. Sometimes a heavy storm and wind can force rainwater inside the bathroom vent, eventually dripping into the bathroom. 

If a bathroom exhaust vent isn’t properly terminated at a suitable height, melting ice and snow can cause water to drip through the exhaust vent. However, warm exhaust air coming outside from the vent usually melts the surrounding snow that drips into the exhaust vent.

5. Older exhaust fans

Old exhaust fans will wear out, just like any other equipment in your home. If you aren’t cleaning your bathroom exhaust fan regularly, or if it has been left running for long periods regularly, it will eventually break down and have to be replaced.

Older fans cannot perform their function efficiently, so moist and humid air gets trapped in the exhaust duct instead of being let out to the exterior. This trapped air eventually will condensate, and the water will leak through the exhaust fan. 

Is it important to fix water dripping from the bathroom exhaust fan?

An exhaust is installed to eliminate the bathroom’s moisture and odors. A dripping exhaust fan increases the moisture and humidity in the bathroom instead of decreasing it. It is important to fix water dripping from the bathroom exhaust fan because water dripping can cause damage to your attic and rot woodwork. It not only cause water damage to your property internally, but it causes visible stains on the ceiling. It also promotes mold growth with continuous moisture seeping around the exhaust fan vent, which can be exceptionally bad for residents with breathing problems. In short, when not fixed promptly, water leaking through your bathroom vent fan could cost you hundreds of dollars over time in repairs. 

How to stop bathroom exhaust fan from dripping

A dripping exhaust fan can be frustrating and might also be causing damage to your house structure with moisture and mold. Plus, it can shorten your exhaust fan’s lifespan. Here are some simple solutions to fix the leaking exhaust fan. 

1. Replace existing insulation

Sometimes insulation slips down the ventilation pipe, which can cause condensation. To stop your bathroom exhaust fan from dripping, you’ll want to replace any existing insulation with a high-quality option. It can be tricky, so if you don’t have experience in home improvement projects, it may be best to work with a contractor or professional handyman. It is an essential step in preventing water damage and other issues in your bathroom!

2. Clear vent blockage

Before heading into your attic, clear any obstructions clogging your vent line. It could be something as small as a bit of lint or a leaf blowing in through an open window. If you suspect an obstruction is causing drips, open the fan grill and examine. Mostly lint formation on the parts of the exhaust fan and the vent entrance is the cause of poor airflow. Regularly cleaning up the exhaust fan will prevent water from dripping in many cases.

Moreover, ensure your air filter fits snugly into its case and isn’t blocking off any of its vents. A loose or obstructed filter can cause excess moisture build-up, which will lead to dripping. Refer to the manufacturer’s manual to see if everything has been installed properly.

3. Keep the exhaust fan clean

Dust buildup on the fan motor can compromise the efficiency of the exhaust fan in removing moisture from the bathroom. You should perform a thorough cleaning of the fan motor and fan cover at least once a year. However, cleaning it twice a year will keep the fan in better working condition.

Cleaning an exhaust fan inside out doesn’t require too much of your time, and the results are astonishing. In many cases, fan cleaning will solve the issue of water dripping.

4. Replace the roof vent cover

Do you only notice your exhaust fan dripping when it rains heavily? Most probably, a damaged vent cover on the roof is causing water to seep into the vent and drip into your bathroom through the exhaust fan. In that case, go to the roof and physically check the roof vent cover. Check to see if it’s cracked or has tears, as these can lead water into your exhaust fan. If you find any damage, replace it with a new vent cover.

If you can’t find any damage, it is a chance that it hasn’t been installed properly. Consult a professional to examine and replace it before it causes any serious damage to your roof and house structure.

5. Replace an inefficient exhaust fan

It may seem like a simple solution, but it’s one of our best. If your exhaust fan has developed a drip, chances are it’s not doing its job properly—probably because it isn’t powerful enough for your bathroom. When you choose a new fan for your bathroom, get one that matches your specific needs—and save yourself some water and money in your wallet.

Additional tips to prevent water dripping from the bathroom exhaust fan

It’s better to take some precautions before any serious problem develops. If you plan to install a new exhaust fan, follow these simple tips to avoid a leaky exhaust fan in the future.

Choose an exhaust fan according to your needs

When choosing an exhaust fan, ensure it’s big enough to accommodate your family’s bathroom usage. While an excessively large fan isn’t good for energy efficiency (it requires more electricity), a too-small unit will result in multiple issues—including serious water damage. As more moisture will build up with more people using the bathroom, choose an exhaust fan that can work heavy duty.

Install it in a strategic location

Ensure your exhaust fan is placed where it can suck up steam and moisture. A strategically placed bathroom exhaust fan can help prevent mildew and mold. Placing it near your bathtub or shower, for example, helps suck up wet air immediately. A little care goes a long way in maintaining a healthy space for your family to use!

Run the fan effectively

Most manufacturers recommend running your exhaust fan for at least 15 minutes after taking a shower or bath. It will ensure that all excess moisture has time to evaporate and doesn’t settle on surfaces like tiles and counters. However, it doesn’t mean you don’t run the fan while taking a shower or a hot bath! Turn the fan on before filling your tub with water, so the steam is thrown out to the exterior as soon as you open the faucet.

You can also opt for a humidity-detecting exhaust fan which starts automatically as the humidity level reaches a certain point hence keeping the moisture in the bathroom under control.

Install a dehumidifier

One of the most common causes of dripping is improper humidity levels. If your bathroom exhaust fan is dripping because of humidity, you might be able to fix it by installing a dehumidifier. Dehumidifiers suck up excess moisture in a room’s air, reducing condensation. You might also want to consider investing in more dehumidifiers for the rest of the house if you live in a climate where humidity is an issue. 


You’ve probably seen water dripping from your bathroom exhaust fan before. It can be awkward, especially if you are a neat freak. But you don’t have to worry as in most cases as there are simple reasons for water dripping, simple solutions can prevent that. Also, consider the tips provided in the article to decrease humidity levels in your bathroom for better functioning of your exhaust fan.

However, no amount of prevention can guarantee that your bathroom exhaust fan will never drip. Implementing these tips and checking your exhaust fan often should keep it running smoothly for years. But if you’re experiencing significant water dripping through your exhaust fan, shut it off immediately and call a professional.

Charles John

Experienced HVAC technician with 8 years of experience in the industry. Capable of handling all sorts of heating and cooling equipment as well as proficient in operational management, construction-related techniques such as preventative maintenance, electrical troubleshooting and AutoCAD

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