What you should consider when buying a bath fan or home ventilation system.
Steamy mirrors, damp walls and fogged windows. They’re more than annoying. They could indicate developing problems like mold and mildew, ruined insulation and wood rot. Spot ventilation solutions from Broan clear the air quickly and efficiently removing potential problems before they invite themselves into your home.
What’s in stays in today’s airtight homes. Today’s homes are built airtight for efficiency. But that means moisture and airborne pollutants say where they are unless they are vented away. Eliminating excess moisture keeps your home dry and comfortable and can help avoid mold and mildew. Volatile organic compounds (VOCs) “outgas” from construction materials such as plywood, carpet, fabric, paint, adhesive, insulation and other common items. Allergens, dust, cooking vapor and what the kids bring home from school are more reasons why good ventilation is critical.
Which product is best suited to my application? Take a moment to consider what you’re looking for in a spot ventilation product. Do you want quiet operation a powerful blower, decorative designs or something that’s virtually invisible? Could you use more light or ventilation in a walk in closet? Broan has what you need.
Sones measure the “sound level” of your fan. A sone is a measurement of sound in terms of comfortable hearing level for an average listener. The lower the sone value the more comfortable the environment. Sones are not decibels or volume but rather how sound is “sensed.” One sone is half as loud as two sones and is equivalent to a quiet refrigerator.
Proper installation makes all the difference.
Tape or caulk around the seam where the fan housing meets the sheetrock on the ceiling.
If possible use smooth rigid ductwork as large as the exit opening on the body of the fan housing.
Whether rigid or flex duct the turning radius for the duct should be as large as possible.
Whenever possible, ductwork should slope down and away from the fan housing to direct any condensation toward the vent.
Keyhole slots and alignment tabs facilitate installation taking the guesswork out of proper mounting.
Elbows, turns, long ducts and ductwork smaller than the fan’s exit outlet will reduce performance.
Use wide aluminum foil or duct tape to join smooth metal ductwork seams.
Do not let flexible ductwork sag as this impedes airflow.
During installation orient the bath fan outlet in the direction of the home’s exit point to minimize duct turns.
Before adding an elbow or bend allow 24” to 36” of straight run from the fan outlet point.
Duct wrap insulation (R-5 or above) will help minimize condensation in cold climates especially on long duct runs.
Exit vents should have back draft flaps to help keep cold air from entering the duct.
Easy steps for choosing and sizing the right ventilation fan for your home.
Determine which rooms could use ventilation and how much is needed.
Spot ventilation is used in localized areas to remove moisture, odor and airborne pollutants quickly. Most commonly used in the bath or powder room, spot ventilation can also be used in a laundry room, exercise area, closet or bedroom wherever air should be changed frequently. Decorative and recessed models can be ideal solutions for these situations. According to the Home Ventilating Institute, Air Changes per Hour (ACH) for comfortable and healthy living should be as follows: Bathrooms: 8 changes, Kitchens:15 changes, Living/Bedrooms:6 changes. Broan bath fans, utility fans and high capacity fans meet these needs.
Calculate the air movement necessary for proper ventilation. Air movement is measured in Cubic Feet per Minute (CFM). To determine CFM requirements, first determine the size of your room. Measure and multiply the length width and ceiling height of your room to determine cubic footage. Then use the multiplication factor of .13 and round up to the next “ten.” See the three examples that follow.
Example 1: Bathroom with 8’ ceiling: 7’ wide x 9’ long x 8’ high x .13 = 66. Select a bath fan with at least 70 CFM.
Example 2: Bathroom with 9’ ceiling: 10’ wide x 9’ long x 8’ high x .13 = 105. Select a bath fan with at least 110 CFM.
Example 3: For a bathroom with a vaulted ceiling use the average ceiling height at the wall and the peak: 8’ wide x 12’ long x ((8’ at wall + 12’ at peak)/2 = 10’) average height x .13 = 125. Select a fan(s) with at least 130 CFM.
Account for long duct runs and ductwork that turns before it reaches the exterior vent.
When airflow is restricted in any way it slows down. Just as a car must slow down for a sharp corner, air decelerates when going through a turn in a duct run. Whenever possible, create a straight duct run with large radius turns, if they’re necessary at all. Rigid ductwork is optimal because airflow restriction is minimized. Flexible tubing may be convenient to install, but resistance is created as air is moved over the spiral metal frame of the tubing. With long duct runs or ducts with multiple turns the fan works harder, noise increases and fan performance (CFM) is compromised. Select a fan model with an even greater CFM rating compensates.
6” ducting overcomes most performance related installation issues. Broan’s QTX series fans deliver high performance in virtually any real world installation. They are engineered with a 6” duct connector for peak air movement and extremely quiet operation, even when the duct run is not short and straight.
Everything you need to know about home ventilation.
What is a sone, and how is it measured?
A sone is a measurement of sound in terms of comfortable hearing level for an average listener. The lower the sone value, the more comfortable the listening environment. Sones are not decibels or volume but rather how sound is “sensed.” One sone is the equivalent of a quiet refrigerator.
What does CFM mean?
CFM is the acronym for Cubic Feet per Minute the measure of air volume moved by the fan blower. Choose a fan with a CFM rating appropriate for your room size to ensure adequate ventilation.
What is continuous ventilation?
Continuous ventilation provides today’s airtight homes with a relatively constant and controlled lower level of ventilation. Broan’s extremely quiet and efficient Ultra Silent Series is ideally suited for these applications.
Can I mount Broan fans above my tub and shower?
Most Broan fans are rated for use over a shower or bathtub with a GFCI (Ground Fault Circuit Interrupter).
Can my bath fan be surrounded by insulation?
Yes. Broan bath fans are designed to provide adequate cooling for motors and lighting as well as products with integral heaters.
Will Broan fans work in wall mount application?
Some Broan bath and utility fans may be wall mounted. See the product matrix for specific models. Improper installation may affect fan life safety and your warranty.
Will a bath fan or wall mount utility fan serve as a range hood?
No. Range hoods are specifically designed to handle grease and high temperature environments. Broan bath fans supplement odor and moisture removal in the kitchen but are not intended for use as a range hood.
What does “static pressure” mean?
Static pressure is the measurement of airflow resistance as it is pushed through ductwork which reduces the effectiveness of the fan. Learn more on the Home Ventilating Institute web site www.hvi.org.
How long should a bath fan run after a shower is used?
The Home Ventilating Institute recommends that a fan should be left on for 20 minutes more to clear humidity adequately and to ensure moisture and condensation in the fan body or ducting in minimized.
What should I do if I can’t wait for moisture to clear, but I don’t want a fan to run all day long?
Broan has sensing fans that detect the humidity rise caused by a shower and turn on automatically when moisture has cleared it turns off. Some wall controls also give you the option of humidity sensing or timer control. Just set it and forget it.
What are the timer features?
Delay off timers automatically shut your fan off after a specified time interval. It’s nice feature in ihgh traffic bathrooms where you may wish to let the fan run to clear moisture adequately. A timer counts down the minutes of fan operation selected by the user.
Where should the exhaust fan be located?
Exhaust fans should be located in or near the shower or tub and in an enclosed water closet. Keep exhaust points opposite the supply air is drawn through the room. Bathroom doors should not be sealed too tightly at the bottom in order to allow “makeup air” to enter the room when the door is closed.
Where is the exhaust outlet on the ventilation fan?
The exhaust outlet is the point where air is discharged through the body of the fan housing into the ductwork. During installation orient your fan with the exhaust outlet pointing toward the exit vent on your roof or wall to minimize turns in ductwork that impede airflow.
Why do the windows and mirrors fog even when the fan is running?
If windows and mirrors are very cold condensation can still form on these surfaces. And if your bathroom is seal tightly replacement air may not be entering the room fast enough to displace the moist air. Be sure to undercut your door sufficiently to undercut your door sufficiently to draw fresh air into the room. Fan placement can also be a factor. Your fan should be located far from the replacement air source to ensure the moist air is drawn out first. Finally too many twists and turns in the ducting will significantly reduce the ability of the blower to remove moist air. Make sure your ductwork is as short and straight as it can be with gradual turns rather than tight corners where necessary.
Why is water dripping from the grille of the fan?
Dripping water is either condensation (usually due to cold ductwork or improper duct installation) or a problem with the seal on a wall or roof vent. Insulated ductwork can help solve condensation problems and running the fan longer will ensure moisture is completely removed from the duct. Ductwork should slope down toward a wall vent direct condensation out of the exterior vent opening rather than back into the fan housing.
Can I install a heater over the bathtub or in a shower?
No. Heaters are not UL Listed (Underwriter’s Laboratory) for installation over a bathtub or in a shower.
Can I use an inline or multi port fan in one large bathroom?
Yes, this works the best for large rooms because you can install the ports over the areas where the ventilation is needed the most (source control). The size of the multi port would be determined by the size of the room.
Does a duct free bath fan expel air?
No. A duct free fan is not a ventilating device. It does not remove air from the room.
Can larger diameter ducting be used with my bath fan?
Yes, larger diameters will result in improved performance.
Can I use smaller diameter duct that what the fan is designed for?
This is not recommended. It will cause the fan to run harder greatly reducing the CFM performance of the fan and create excess noise.
What type of duct is recommended, rigid or flexible?
It is recommended where possible to use rigid duct. It has less resistance to air flow and allows the fan to operate much more efficiently. If aluminum flexible duct is used be sure the duct is as straight as possible.
Can I exhaust my fan into my attic instead of out the roof or wall?
Never exhaust air into spaces within walls, ceilings, attics, crawl spaces or garages. Humidity may damage the structure and insulation.
What type of exhaust fan is best for a sauna or hot tube area?
High CFM rated devices are normally recommended for this type of application.
Can I use a fan in a steam shower?
No. Since these are normally sealed chambers a vacuum will be created.
Can I vent more than one bath fan out of a roof or wall cap?
No. Always follow the manufacturer’s recommended ventilation requirements.
Steamy mirrors, damp walls and fogged windows. They’re more than annoying. They could indicate developing problems like mold and mildew, ruined insulation and wood rot. Spot ventilation solutions from Broan clear the air quickly and efficiently removing potential problems before they invite themselves into your home.
What’s in stays in today’s airtight homes. Today’s homes are built airtight for efficiency. But that means moisture and airborne pollutants say where they are unless they are vented away. Eliminating excess moisture keeps your home dry and comfortable and can help avoid mold and mildew. Volatile organic compounds (VOCs) “outgas” from construction materials such as plywood, carpet, fabric, paint, adhesive, insulation and other common items. Allergens, dust, cooking vapor and what the kids bring home from school are more reasons why good ventilation is critical.
Which product is best suited to my application? Take a moment to consider what you’re looking for in a spot ventilation product. Do you want quiet operation a powerful blower, decorative designs or something that’s virtually invisible? Could you use more light or ventilation in a walk in closet? Broan has what you need.
Sones measure the “sound level” of your fan. A sone is a measurement of sound in terms of comfortable hearing level for an average listener. The lower the sone value the more comfortable the environment. Sones are not decibels or volume but rather how sound is “sensed.” One sone is half as loud as two sones and is equivalent to a quiet refrigerator.
Proper installation makes all the difference.
Easy steps for choosing and sizing the right ventilation fan for your home.
Determine which rooms could use ventilation and how much is needed.
Spot ventilation is used in localized areas to remove moisture, odor and airborne pollutants quickly. Most commonly used in the bath or powder room, spot ventilation can also be used in a laundry room, exercise area, closet or bedroom wherever air should be changed frequently. Decorative and recessed models can be ideal solutions for these situations. According to the Home Ventilating Institute, Air Changes per Hour (ACH) for comfortable and healthy living should be as follows: Bathrooms: 8 changes, Kitchens:15 changes, Living/Bedrooms:6 changes. Broan bath fans, utility fans and high capacity fans meet these needs.
Calculate the air movement necessary for proper ventilation. Air movement is measured in Cubic Feet per Minute (CFM). To determine CFM requirements, first determine the size of your room. Measure and multiply the length width and ceiling height of your room to determine cubic footage. Then use the multiplication factor of .13 and round up to the next “ten.” See the three examples that follow.
Account for long duct runs and ductwork that turns before it reaches the exterior vent.
When airflow is restricted in any way it slows down. Just as a car must slow down for a sharp corner, air decelerates when going through a turn in a duct run. Whenever possible, create a straight duct run with large radius turns, if they’re necessary at all. Rigid ductwork is optimal because airflow restriction is minimized. Flexible tubing may be convenient to install, but resistance is created as air is moved over the spiral metal frame of the tubing. With long duct runs or ducts with multiple turns the fan works harder, noise increases and fan performance (CFM) is compromised. Select a fan model with an even greater CFM rating compensates.
6” ducting overcomes most performance related installation issues. Broan’s QTX series fans deliver high performance in virtually any real world installation. They are engineered with a 6” duct connector for peak air movement and extremely quiet operation, even when the duct run is not short and straight.
Everything you need to know about home ventilation.
What is a sone, and how is it measured?
A sone is a measurement of sound in terms of comfortable hearing level for an average listener. The lower the sone value, the more comfortable the listening environment. Sones are not decibels or volume but rather how sound is “sensed.” One sone is the equivalent of a quiet refrigerator.
What does CFM mean?
CFM is the acronym for Cubic Feet per Minute the measure of air volume moved by the fan blower. Choose a fan with a CFM rating appropriate for your room size to ensure adequate ventilation.
What is continuous ventilation?
Continuous ventilation provides today’s airtight homes with a relatively constant and controlled lower level of ventilation. Broan’s extremely quiet and efficient Ultra Silent Series is ideally suited for these applications.
Can I mount Broan fans above my tub and shower?
Most Broan fans are rated for use over a shower or bathtub with a GFCI (Ground Fault Circuit Interrupter).
Can my bath fan be surrounded by insulation?
Yes. Broan bath fans are designed to provide adequate cooling for motors and lighting as well as products with integral heaters.
Will Broan fans work in wall mount application?
Some Broan bath and utility fans may be wall mounted. See the product matrix for specific models. Improper installation may affect fan life safety and your warranty.
Will a bath fan or wall mount utility fan serve as a range hood?
No. Range hoods are specifically designed to handle grease and high temperature environments. Broan bath fans supplement odor and moisture removal in the kitchen but are not intended for use as a range hood.
What does “static pressure” mean?
Static pressure is the measurement of airflow resistance as it is pushed through ductwork which reduces the effectiveness of the fan. Learn more on the Home Ventilating Institute web site www.hvi.org.
How long should a bath fan run after a shower is used?
The Home Ventilating Institute recommends that a fan should be left on for 20 minutes more to clear humidity adequately and to ensure moisture and condensation in the fan body or ducting in minimized.
What should I do if I can’t wait for moisture to clear, but I don’t want a fan to run all day long?
Broan has sensing fans that detect the humidity rise caused by a shower and turn on automatically when moisture has cleared it turns off. Some wall controls also give you the option of humidity sensing or timer control. Just set it and forget it.
What are the timer features?
Delay off timers automatically shut your fan off after a specified time interval. It’s nice feature in ihgh traffic bathrooms where you may wish to let the fan run to clear moisture adequately. A timer counts down the minutes of fan operation selected by the user.
Where should the exhaust fan be located?
Exhaust fans should be located in or near the shower or tub and in an enclosed water closet. Keep exhaust points opposite the supply air is drawn through the room. Bathroom doors should not be sealed too tightly at the bottom in order to allow “makeup air” to enter the room when the door is closed.
Where is the exhaust outlet on the ventilation fan?
The exhaust outlet is the point where air is discharged through the body of the fan housing into the ductwork. During installation orient your fan with the exhaust outlet pointing toward the exit vent on your roof or wall to minimize turns in ductwork that impede airflow.
Why do the windows and mirrors fog even when the fan is running?
If windows and mirrors are very cold condensation can still form on these surfaces. And if your bathroom is seal tightly replacement air may not be entering the room fast enough to displace the moist air. Be sure to undercut your door sufficiently to undercut your door sufficiently to draw fresh air into the room. Fan placement can also be a factor. Your fan should be located far from the replacement air source to ensure the moist air is drawn out first. Finally too many twists and turns in the ducting will significantly reduce the ability of the blower to remove moist air. Make sure your ductwork is as short and straight as it can be with gradual turns rather than tight corners where necessary.
Why is water dripping from the grille of the fan?
Dripping water is either condensation (usually due to cold ductwork or improper duct installation) or a problem with the seal on a wall or roof vent. Insulated ductwork can help solve condensation problems and running the fan longer will ensure moisture is completely removed from the duct. Ductwork should slope down toward a wall vent direct condensation out of the exterior vent opening rather than back into the fan housing.
Can I install a heater over the bathtub or in a shower?
No. Heaters are not UL Listed (Underwriter’s Laboratory) for installation over a bathtub or in a shower.
Can I use an inline or multi port fan in one large bathroom?
Yes, this works the best for large rooms because you can install the ports over the areas where the ventilation is needed the most (source control). The size of the multi port would be determined by the size of the room.
Does a duct free bath fan expel air?
No. A duct free fan is not a ventilating device. It does not remove air from the room.
Can larger diameter ducting be used with my bath fan?
Yes, larger diameters will result in improved performance.
Can I use smaller diameter duct that what the fan is designed for?
This is not recommended. It will cause the fan to run harder greatly reducing the CFM performance of the fan and create excess noise.
What type of duct is recommended, rigid or flexible?
It is recommended where possible to use rigid duct. It has less resistance to air flow and allows the fan to operate much more efficiently. If aluminum flexible duct is used be sure the duct is as straight as possible.
Can I exhaust my fan into my attic instead of out the roof or wall?
Never exhaust air into spaces within walls, ceilings, attics, crawl spaces or garages. Humidity may damage the structure and insulation.
What type of exhaust fan is best for a sauna or hot tube area?
High CFM rated devices are normally recommended for this type of application.
Can I use a fan in a steam shower?
No. Since these are normally sealed chambers a vacuum will be created.
Can I vent more than one bath fan out of a roof or wall cap?
No. Always follow the manufacturer’s recommended ventilation requirements.
