Wooden bathroom interior with sink and mirror, shower on podium, white tub and foot towel on hardwood floor. Bathing accessories on shelf. 3D rendering

Bathroom Ventilation

1. Why would I want/need a bathroom fan?

A bathroom fan removes moisture that produces mold and contributes to poor Indoor Air Quality (IAQ). Bathroom ventilation helps remove unwanted odors, and in some regions, IAQ requirements state bath fans must expel a certain amount of CFM/hour or CFM/day.

2. How do I select the right Fantech Premium Bath Fan for my bathroom?

According to the guidelines of the Home Ventilating Institute (HVI), baths that are 100 sq. ft. or smaller require 1 cfm per square foot of bathroom floor area with a minimum 50 cfm exhaust rate. To find the square footage simply multiply the length of the bathroom by the width. Allow 50 cfm per standard tub, shower, or toilet. Calculate whirlpool, garden, and jetted tubs at 100 cfm.

Example 1: Bathroom 9’ x 7’ = 63 sq. ft. you require the PB110 or PBW110.

Example 2: Bathroom 11’ x 14’ = 154 sq ft, 1 Toilet + 1 Shower + 1 Tub = 150 CFM; therefore, you require the PB270L10-2.

Note: HVI recommends that steam showers use a separate fan on a timer so that you can shut off the fan during shower use and run the fan afterwards to dry out the shower stall. For proper airflow in typical installations (when duct losses are not calculated), use the 0.4” Pst rating point for the correct fan selection. Pst, or static pressure, is a measure of resistance to airflow as a fan pushes or pulls air through a duct. It is measured in inches of water gauge, such as 0.1” w.g. This method shows the resistance is equal to raising a column of water 0.1” or one-tenth of an inch.

To allow for makeup air, bathroom doors should be undercut at least ¾” to allow clearance over the finished floor.

Use our bathroom fan selector at bathfan.fantech.app to find a product that suits your project.

3. How many bathrooms can I vent with one fan?

Fantech recommends that no more than 3 bathrooms use the same bath fan. Whenever the fan runs, air exhausts from all rooms connected to the single system. This, in combination with the much higher cost of large fans, means that it is generally beneficial to exhaust a maximum of three smaller, or two larger, bathrooms together.

Check out the video “Fantech Bathroom Exhaust Fan” by “Ask the Builder” to learn more about this topic and our bathroom fans.

4. Is there a way to replace my existing noisy bath fan with a Fantech Premium Bath fan without having to drywall the bathroom ceiling?

Installing a Fantech Bath Retrofit Kit (BFRK100) is an easy way to convert your noisy bath fan into a quiet yet powerful ventilation system. The kit includes an inline fan, fittings, and accessories. Your existing fan grille and housing will stay in place. No drywall work needed, and Fantech offers easy to follow instructions to show you how.

Check out the video “Bath fan Retrofit Kit (BFRK)” for additional details.

5. I do not have room to install a remote inline fan in my application. Is there another fan I could use?

For this problem, Fantech offers the PBW 110 that comes with a ceiling grille and externally mounted fan. It is ideal for basement bathrooms and first floor powder rooms.

6. Can I use my Fantech Premium Bath Fan to provide continuous ventilation?

Yes. When used with the Fantech Fan Control Sensor, your PB fan may provide a cost-effective way to comply with your specific code requirements regarding controlled ventilation in residential applications. Check out our ⁣VT20M bath fan switch to help provide your home with continuous ventilation.

7. How many auxiliary controls (VT20A) can be used with one Master Control (VT20M)?

Four VT20A auxiliary controls can be used with one VT20M. This allows ventilation in areas such as bathrooms, laundry rooms, workshops, etc. The VT20A is connected to the VT20M with a 2-core insulated cable.

8. Can I add a motion sensor to a Fantech Bathroom Exhaust Fan?

Yes, any motion sensor that matches voltage requirements will operate the Fantech fan.

9. What installation tips can you give me to get the most from my Fantech Premium Bath fan?

  • Keep the duct runs as short as practical (under 25 feet).

  • Ensure the inner core of the flexible insulated ducting stays as tight and as straight as possible.

  • Seal the ducting to the grille housing/fan/wye connector/termination with aluminum foil tape.

  • Ensure there is a minimum of 3 duct diameters between any fitting and the inlet/outlet of the fan.

  • For the PB270L10-2 and PB370, It is better to have a short run of larger trunk line from the wye connector to the inlet of the fan and from the fan outlet to the termination point.

  • In addition, Fantech recommends using longer runs of smaller duct from the grille/light to the wye connector.

10. Can I insulate my Fantech Premium Bath Fan grille/light housing with insulation?

Yes, the grille/light units are Insulation Contact (IC) rated.

11. Can I mount the fan horizontally?

Yes, the orientation of the fan will not affect its operation. When running horizontal duct to the outside, Fantech recommends slightly angling the duct down to the outside vent to allow condensation (if any) to naturally run out of the duct.

12. Can I install Fantech Premium Bath Fans with LED or Halogen grilles/lights over a tub or a shower?

Yes. Both the LED and Halogen grille/lights are UL listed for wet locations. When installed over a tub or shower, connect the fan to a Ground Fault Circuit Interrupter (GFCI) to prevent electrical injury.

13. Can I turn on my light separate from my fan?

Yes, Fantech recommends wiring the light on its own switch, and wiring the fan on a timer such as the Fantech FD60EM or a humidity control unit like the ⁣DHS 05

14. Should I run the fan after I have finished in the shower?

Yes. The Home Ventilating Institute (HVI) recommends running the fan for a minimum of 20 minutes after using the bathroom to completely exhaust moisture. Fantech offers a line of humidity sensors, programmable & manual controls, timers, and switches for your convenience.

15) Can I paint Fantech plastic grilles?

Yes, you can. Fantech recommends using a paint that is suitable for plastic. An example of such paint is “Krylon Fusion for Plastic”. If you use a paint unsuitable for paint plastic, apply a primer coat of paint suitable for plastic first. An example of such paint is “Rust-oleum Specialty Plastic Primer”. Applying unsuitable paint directly to our plastic grilles will likely not yield satisfactory results.

Before painting, remove the grille from the installation to prevent paint spilling over the lamp socket contacts, damper flap, or labels. As with all painting processes, Fantech recommends proper cleaning and following the directions of the paint manufacturer to ensure a higher quality painted grille.

16. What is the Warranty on Premium Bath Fans?

Fantech Premium Bath Fan Warranty is 7 years.