How Long Should Bath Fan Run After Shower

We all know the importance of running a bathroom exhaust fan during a shower or steamy bathroom. But did you know that turning your fan off right later on you have finished showering agency that it is exclusively partially effective?

What makes running a bathroom fan later a shower necessary? What does it hateful if a bath is notwithstanding steamy later on the recommended time period? Should a bath fan live function continuously for the best protection against moisture build-up? I furnish y'all amongst answers to these questions and more than inward the next sections.  

The Home Ventilation Institute recommends running a bath fan for at least twenty minutes later showering. This ensures all the moisture has been pulled from the bath in addition to vented out of the ducts. Using a bath fan timer switch can ensure that your fan ever runs the optimal amount of fourth dimension.

Recommended Bathroom Fan Ventilation Duration 

According to the Home Ventilation Institute (HVI), for a bathroom to live adequately ventilated, it needs to undergo some 8 air changes per hr. The HVI recommends two-3 air changes or running the fan for twenty minutes afterward showering to take all the steam from the bathroom afterwards a shower.

Why Should the Fan Be Left to Run After a Shower?

There are two principal reasons why the fan should be allowed to operate in one case you lot are done inwards the shower.

Steam Is Typically Generated Faster Than It Is Exhausted

Most people switch on the fan correct before getting inward the shower (or a few minutes afterwards realizing they forgot) as well as switch it off at once later the shower. However, this would only work if the rate of steam production straight matched the rate at which air is exhausted. In reality, steam is generated faster than it is exhausted.

Furthermore, it is non entirely the steam y'all take to consider. If at that place is wet on the walls or other surfaces equally a consequence of condensation or splashing, this wet tin can evaporate into the air in the time next your shower.

This does not look like rolling clouds of steam, merely it is, nevertheless detrimental to your bath. Running the bathroom fan for twenty minutes longer than you lot are inwards the shower allows moisture removal while the bath surfaces dry.

If there’second anything that tin can movement a listing of damages to your bath, it is wet, and then if an extra 20 minutes tin can salvage us from warped doors, rusted fixtures, peeling paint together with wallpaper, as well as increase of mold, then I, for ane, am not complaining!

Running the Fan Ensures the Air Is Exhausted Outside

The International Residential Code, Section M1505.ii prohibits exhausting bath and can room air to anywhere other than outside of the household. This involves the use of diverse lengths of ducting.

Turning the bathroom fan on creates the force per unit area organization required to move the air along the duct and out of the family. However, if y'all turn off the fan prematurely, the moist air remains inward the duct too doesn’t get completely exhausted, or it may accept longer to kick the bucket the ductwork.

The longer the air remains inwards the duct, the more fourth dimension it has to cool downward. This allows the wet to condense out too sit inward the ducts or drip out of your bath fan after your shower.

Over fourth dimension, this tin effect inwards issues similar rust or mold inside the ventilation organisation. This can terminate upwardly compromising indoor air character in addition to putting your family unit members’ wellness at run a risk of all kinds of diseases.

What if the Bathroom Is Still Steamy After xx Minutes?

The exhaust fan is in that location to remove the steam completely from your bath. If the bathroom is withal steamy afterwards xx minutes, and so it indicates a problem amongst the ventilation inward the bath. Let us await at the diverse reasons that could movement this.

Check out the graph below. This is from my home. I used to have an underpowered bath fan. It took well-nigh 2 hours for the humidity level to normalize after a shower.

Is the Fan Strong Enough for the Bathroom?

When it comes to deciding on an exhaust fan, you must go along the size of your bathroom inward heed. If a fan is besides pocket-sized for your bathroom, it volition live incapable of removing the steam efficiently within the xx minutes.

The size of your bathroom determines the appropriate CFM (cubic feet per minute) rating of the fan yous need inwards your bathroom. The ideal airflow needs to live at to the lowest degree 1 CFM per square foot of bath expanse.

But don’t be frightened off by the idea of doing math! I have created an tardily-to-role CFM Calculator that volition say you inwards a few seconds the exact size y'all ask to install for efficient ventilation.

Fan May Be Functioning Sub-Optimally

If your bathroom fan is sized correctly, just at that place is even so steam lingering subsequently twenty minutes, it can signal that your fan is non operation correctly.

Sometimes this is the issue of historic period (10 years is the average lifespan of a bath exhaust fan), which causes natural habiliment together with tear on the motor, electrics, blades, etc. But it besides mightiness be something as simple as dirt.

Like every other electrical appliance, your bath fan needs proper attention as well as regular cleaning. The fan blades are unremarkably moist while venting the steam out of the house. Over time the dust inward the air deposits on the blades as well as affects the fan’s efficiency.

You must clean your bathroom fan at to the lowest degree once every half-dozen months. Don’t forget that a dingy together with lint-filled bathroom fan is not but inefficient, but it is also a burn hazard.

Fan Location Can Make a Difference

Technically, the bathroom fan will vent the moist air exterior no thing where it is placed. But for maximum efficiency, it’s best to set the bath fan on the ceiling inward or well-nigh the shower.

Hot air rises, and so ceiling insert fans make a lot of practical feel. And placing the fan in a higher place or virtually the shower is besides logical equally this is the principal rootage of steam, so it is exhausted before it can spread also far.

However, it should be noted that placing the fan straight above the shower can make showering chillier, peculiarly in wintertime, every bit it creates a breeze.

If you lot desire to notice out more most the best location for your bathroom fan, and then cheque out this article that volition sure benefit yous.

Temporary Solutions to Ineffective Bathroom Fans

You need to address the underlying drive as to why your bath is however steamy later on twenty minutes, simply until yous are able to make so, hither are a few temporary solutions that can aid:

• Open the door in addition to window during too after showering.
• Use a floor dehumidifier.
• Put out containers of wet-absorbing powders.
• Wipe the walls afterwards showering.
• Use a regular pedestal fan to create airflow.
• Dry your towels outside the bath and so that they do non contribute to the wet content of the air.

Problems With Running Your Bathroom Fan for Too Long

Although running your bath fan during your shower too for 20 minutes afterwards is of import, this does not mean that leaving it on indefinitely is the best selection.

There Is a Financial Cost

If used when necessary, the average cost of running a modern, correctly sized fan is $iii.five per year, in addition to for a heated bathroom fan, it is $113 per twelvemonth. But if the fan runs longer than required, and then your electricity nib volition surely ascent.

Furthermore, overtaxed fans depict more than energy, too continuous role will shorten the fan’s lifespan, necessitating early on replacement. 

Using a bath exhaust fan as well long when the dwelling is beingness heated or cooled volition drastically increment the free energy neb. There is considerable estrus loss from the running fan. A 20-xxx minute runtime to exhaust wet is OK. However, when the fan is running for hours, there volition be significant oestrus loss.

There Is a Safety Risk

It has been proven that running a fan 24/seven tin potentially drive a burn down!

In 2017, the U.S.A. Consumer Products Safety Commission (CPSC) did a detailed written report on exhaust fan fires. Based on that study, it’s been made clear that exhaust fans can live dangerous in addition to can drive a fire.

 According to the CPSC report:

 “More than 75 pct (318/423) of the known incidents occurred inwards a bath or restroom. The well-nigh likely source of the incident inward these cases was the exhaust fan. The incidents ranged inward severity from fry fume to fire spreading through the structure. Of the 318 incidents that occurred inward a bath or restroom, nigh 80 pct (254/318) occurred in a residence.”

But how does it movement fires?

Well, excessive running of a bathroom fan results inward thermal wearing. This, in turn, volition eventually movement the fan’sec thermal cutoffs to neglect. Thus, the fan motor temperatures are no longer controlled or capped, together with they tin ascent high enough to ignite and cause a burn down.

In addition, worn bearings together with lint construct-ups effort the motor to overheat in addition to catch fire.

Install a Timer

Some people purposefully go the exhaust fan excessively under the impression that it is beneficial, patch others just forget to plough it off. The best solution is installing a lineament timer that volition salvage money together with free energy too besides ensure your fan lasts longer. 

Install a timer switch that is slow to go together with has multiple timers along amongst upwards-to-appointment wiring to comply alongside the building codes.

Here’sec a list of the best bath fan timer switches that volition sure as shooting cater to your needs.  

Humidity-Sensing Bathroom Fans

Instead of risking forgetting the fan on or getting a bit lazy as well as non bothering to turn it on or leave it operating for long plenty afterwards your shower, yous can buy an exhaust fan alongside a humidity sensor These are absolutely worth it.

If you lot accept a humidity-sensing bath fan, y'all volition take to picket out for whatsoever issues like not turning on when it should or turning on randomly by itself.

Dual Speed Bathroom Exhaust Fans

If you lot want to go your bath fan continuously, and then yous need to purchase a fan that is specifically designed for that role. A bully choice is a dual speed bathroom exhaust fan.

As the refer suggests, these fans function at two speeds. The depression speed is ii or iii times lower than the high speed in addition to is used for continuous ventilation. The high speed is used equally a normal bathroom exhaust fan. It is switched on during the shower together with switched off 20 minutes after showering. 

An advantage of having a fan run continuously is improve indoor air lineament. The constant ventilation brings fresh air from outside inside the dwelling house while pulling out the humid too stale air from the within.