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What Does a Bathroom Fan Do?
Depending on your climate, up to 20 percent of households might be affected by humidity issues. High humidity levels in homes can lead to several problems, both for homeowner health and the building's structural integrity. According to a recent publication by the Environmental Protection Agency (EPA), the ideal indoor relative humidity (RH) for homes should be kept between 30 and 50 percent. When humidity levels rise above 50 percent, mold and mildew growth will almost assuredly begin to grow throughout your home. While we often associate mold with growing on wood, other types of fungi can grow on paper, carpeting, food, and even your insulation when the moisture conditions are correct. Mold and mildew spores are among the leading causes of respiratory diseases, asthma, and other allergies affecting millions of people across the country. In addition, high humidity levels can create ideal conditions for pests such as cockroaches and dust mites.
What is an HVI Certified Bathroom Fan?
HVI Certification for bathroom fans ensures that the product has undergone rigorous performance testing by a third-party organization. The testing required for HVI Certification provides:
- Assurance that independent testing has been completed.
- Confirmation the product will perform as advertised.
- The security that a properly sized and installed model will give the user the right amount of ventilation for the best indoor air quality.
Fans without HVI Certification can inflate their performance ratings and may not always meet building code requirements. HVI Certified bathroom fans are widely available from most major brands, and you can even filter for this attribute when shopping online.
It is worth mentioning that many bathroom fans often come with automatic timers. These allow the bathroom fan to run for 20-25 minutes after someone has taken a hot shower. This timer reduces the energy waste that can occur when the bathroom fan is accidentally left on for extended periods.
What Type of Bathroom Fan Do I Need?
The best type of bathroom fan for your home will depend on the location of your bathroom, the structure and design of your home, and other particular features. Below, we briefly recommend the optimum type of exhaust fan for different kinds of bathrooms.
What Is a Ceiling-Mounted Exhaust Fan?
This type of fan is best for bathrooms located on the upper stories of a home. The exhaust pipe will move up through the attic and vent to the outside through the roof. For this type of fan, it is vital to make sure that the ductwork is vented to the outside. In addition, assure that it is insulated to avoid condensation buildup that could negatively affect the insulation in your attic.
What Is a Wall-Mounted Exhaust Fan?
A wall-mounted exhaust fan is for bathrooms located next to an exterior wall. In this type of installation, the fan is set up on the outside of the outer wall. Wall-mounted exhaust fans offer power ventilation coupled with quiet operation.
What Is a Exterior Exhaust Fan?
An exterior exhaust fan is mounted on the exterior of the home. These are great for reducing noise levels inside the house while regulating moisture to prevent mold and mildew
Do Exhaust Fans Have Lights?
For homeowners who want to improve the aesthetics of their bathroom, exhaust fans that include lighting fixtures are often less of an eyesore and achieve multiple purposes in one unit.
How Do You Calculate the CFM Required for a Bathroom Fan?
Bathroom fans are rated by their cubic foot per minute (CFM) rating. This doesn't necessarily determine the product's energy efficiency as it doesn't look at per-watt usage. However, it can be helpful to size the best fan for your bathroom properly. Most fans come with a CFM rating anywhere between 50 and 110. Homeowners can adequately size the best bathroom fan for their homes by using the following formula:
Minimum CFM rating required = Length x Width x Height (of your bathroom) x 0.13
How Long Do Bathroom Exhaust Fans Last?
Bathroom fans, when properly maintained, will last for an average of ten years. Dusting and cleaning around the fan intake will help avoid the accumulation of dust and debris, which will put more stress on the fan's small motor. If your bathroom fan is noisier than usual, it might be a sign that it is wearing down and needing replacement.
Why Does a Bathroom Fan Make Noise?
Bathroom fans make minor amounts of noise due to the small motors, fans, and blower wheels that help expel the moisture-ridden air. Most new models of bathroom fans will make minimal amounts of noise. However, homeowners who want the most silent fans should opt for exterior exhaust fans mounted on the home's exterior.
How Long Should You Run the Bathroom Fan After a Shower?
The optimum amount of time homeowners should run the bathroom fan after a shower largely depends on the shower's length, the size of the bathroom, and whether or not the bathroom has an operable window. However, the Home Ventilation Institute recommends leaving the bathroom fan running for at least 20 minutes. This time will lower humidity levels and get rid of excessive moisture and condensation levels in the bathroom and in the ductwork that takes the moisture outside the home.
How Do You Maintain a Bathroom Fan?
The accumulation of dust can lead to louder, vibrating noises that are not only annoying to listen to but can reduce the lifespan of your fan. Excess dust can settle on the fan blades or the blower wheel. In the worst-case scenario, this can cause the fan to hit the exhaust housing and produce a loud, banging sound. Regularly cleaning and dusting around the fan intake and the entire housing is the best way to properly maintain your bathroom fan.
Tobias Roberts
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.
