3 Reasons Why Water Is Dripping From The Bathroom Fan

Most homes built within the last two decades almost certainly have an exhaust fan in the bathroom. The primary function of a bathroom fan is to remove all the moisture that accumulates in the bathroom following a shower or bath. However, a bathroom fan may occasionally drip water and this can be caused by several different factors.

In general, water dripping from the bathroom fan is caused by water condensation, due to lack of insulation on the exhaust hose or duct, lack of proper airflow due to vent blockage or improperly installed bathroom fan.

What to check when water is dripping from the fan?

Fortunately, there are a few actions that can be taken to prevent the situation from becoming too severe.

Any bathroom that does not have a window that can be opened to provide ventilation is required to have a bathroom vent fan installed according to the NEC (National Electrical Code) and applicable municipal construction laws. 

Depending on the jurisdiction, it may be necessary even if there are windows present.

Insulation should be replaced or added.

The insulation’s primary function is to separate the warm air that is vented out of the bathroom from the colder air that is found in the attic during the winter. 

This will prevent condensation from forming.

If the weather is cold outside, your air ducts are as well. Condensation will form on the walls of your air duct as a result of this. Therefore, if you see water dripping from your exhaust fan after you have bathed or showered, it is likely that your insulation is the source of your problem, not only the insolation around the ductwork should be considered, but the insolation in your attic might also be insufficient as well. The cold air in the attic and the warm air from the bathroom will cause condensation as well if the hot air isn’t dissipated quickly.

The solution is to replace your existing insulation with more durable and better-fitting insulation materials. The insulation has slipped down the ventilation duct over time, leaving the top portion of the ventilation duct unprotected. Even if you have experience with similar tasks, you may want to hire a professional handyman to complete this one. To guarantee that the insulation is properly installed, a certain level of competence is required.

Check for proper airflow.

Because condensation may quickly build up in a bathroom fan when an exhaust vent is clogged or there is not enough airflow to the outside dripping may occur. To confirm that your fan is working as it should, test it with toilet paper. Take two pieces of toilet paper and fold them in half. Turn on the fan and position the toilet paper near it. The toilet paper should be sucked up by the fan and stick to the vent. If not, your fan is only generating noise. It is not pulling any of the humidity out of the air.

Clean A Dirty Bathroom Exhaust Fan

Having an extremely dirty bathroom fan is similar to having a blocked or damaged bathroom vent and can significantly hinder airflow and may be a contributing factor to the condensation. It can potentially create a fire hazard if not dealt with properly.

The bathroom fan cover often includes a large number of small holes or slots, which may become blocked with dust. If the vent holes are obstructed, the bathroom fan may only be sucking out a small amount of the total volume of moist bathroom air if it is not operating properly.

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Replace the exhaust fan if necessary.

If everything appears to be in working order, you should pay close attention to the bathroom fan itself. It is possible that the fan will not be able to remove all of the moisture due to its capacity.

The capacity may be too low in comparison to the size of the bathroom. If you have a big number of family members who like taking hot showers regularly, a strong exhaust fan will be required to do the job efficiently.

The majority of bathroom fans have a lifespan of between five and ten years. When it comes to removing moisture out of the bathroom, older and slower ventilation fans are less effective than their more modern counterparts. Replacement is required to ensure that your bathroom is free of moisture. 

The exhaust fan must be powerful enough to provide fresh air to the bathroom every 7 1/2 minutes or eight times an hour. This is the accepted industry practice.

Fan Positioning Can Be Modified

The bathroom fan should be located in the bathroom in the area that is subjected to the greatest amount of moisture. In most cases, this refers to the location above the bathtub or shower. The aim of the exhaust fan is largely to remove wet, humid air that might contribute to mold development or moisture damage in the bathroom, and the fan should be installed in an appropriate location where the greatest moisture is present and will ensure that the bathroom exhausts as soon as possible. Though it is possible to install the fan directly over the bathtub or shower base, any location near the bathing area will suffice for this purpose. A fan should be placed anywhere in the bathroom between the tub and the shower, or between the shower and the whirlpool tub if the bathroom includes both fixtures.

Run the fan regularly.

Keep the bathroom fan going while you take a hot shower. Continue to leave it running for at least 10 to 15 minutes after you have finished your shower. 

This will ensure that all of the moisture is removed from your bathroom as soon as possible. There will be no moisture build-up, which will prevent further drips from occurring. A convenient method is to install a humidity detecting bathroom fan to automatically remove and maintain a regulated moisture level in the bathroom.

Typically, the bathroom fan takes warm, moist air from the bathroom and distributes it to the attic through the fan. 

However, keep in mind this condensation accumulates in your attic, and it may result in water seeping through the roof. On a cold day, the moist air will condense on anything that is below its dew point, if the temperature is below zero degrees Celsius. A prolonged period of exposure can result in mold growth and wood decay as well as the attraction of termites and other pests to the area.

 It is therefore important to duct the fan properly to preferably exhaust to the outside away from the building, where possible.

Install a dehumidifier (if needed)

There is a selection of things that might contribute to the moisture problem that is emerging from your bathroom, and you may also be experiencing it in other sections of your home. The climate in which you live may be an added factor to your problem. Install as many dehumidifiers as possible around your home to ensure that you have a level of comfort even on the warmest days of the year when the humidity is at its highest. Considering that a single dehumidifier can only cover so much space, you will want to install a number of them to guarantee that your entire property is protected or invest in an HVAC system with an integrated dehumidifying function.

Roof vent covers should be replaced.

As soon as you discover a bathroom exhaust fan leak, you should check the roof vent cover (louver) to make sure it is not damaged. Nine times out of ten, if the leak only happens during windy and wet conditions, the cover is most likely to be the source of the problem. 

Heavy winds, flying debris, and other outside factors can all cause damage to the louver at different times of the year. Because it is located on your roof, the cover is in an area of your property that is subjected to the most adverse effects of nature.

 If you discover a faulty or damaged vent cover on your roof, this indicates that water can travel through it. To ensure that the roof vent cover is not damaged, you should check it carefully before proceeding. It is possible that the cover has not been damaged, but rather that it has been fitted improperly, resulting in water seeping from the outside of the vent duct opening. 

Have a professional replace the item that has been damaged if you cannot do it yourself.


Moisture and condensate can lead to some real problems around the home and can impact the overall health of the occupants Areas such as kitchens and bathrooms that generate heat from the use of hot water, as well as stoves, must be ventilated properly.