Wayne McCormick
Broker/Owner
Realty Executives of Northern Arizona
Features include lights, controls, sensors
By James Dulley
Question: My bathroom vent fan is noisy and there is a mold problem around the tub, so I think a new vent fan is needed. I want an efficient, quite one. What features should I look for and how big should it be?
Answer: Most older bathroom vent fans were noisy when new and the sound level increases with age.
Bathroom mold and mildew problems are caused by excessive humidity from using a vent fan that is too small or not running it long enough.
Your budget will determine the quality (noise level and features) of the vent fan you select. The top-of-the-line, quietest models with the latest features can cost up to $200. These quiet vent fans are ideal for a bathroom in a master bedroom where another person is trying to sleep.
A new lower-cost option, if you just need somewhat quieter operation and more airflow, is a rebuilding kit for about $20. These kits work in many older Broan and Nutone vent fans that were installed by builders in many homes. The kit includes a modern grille, two motor plates and a new motor.
You have quite a few bathroom vent fan options: fan only, fan/light, fan/light/heater and fan/light/night-light. There are also different types of controls: on-off wall switch, motion-sensing and humidity-sensing.
Humidity-sensing vent fans are most effective and efficient because they come on automatically only when needed and then shut off. This allows you to leave for work without switching off the fan while the bathroom is still too humid. The best models sense the rate of change in humidity as opposed to just to overall humidity level. You can manually override the sensor.
Fan noise level is rated in sones, so compare them for various models. The quietest ones are only 0.3 sones, which is barely audible. Special grille designs and large blades, which turn slower, reduce the sound level. Models designed with a 6-inch duct, instead of the typical 4 inches, are quieter.
Installing a remote in-line fan with multiple ports is another quiet option. If you select a fan/light model, get one that uses fluorescent bulbs for greater-efficiency. To be Energy Star qualified, fan/light models must use these bulbs. Night-light options use only about four watts.
Another lighting option is a new ceiling recessed fan/light. It resembles a standard recessed light but doubles as a vent fan.
Venting tubular skylights for bathrooms are also available. The size of a vent fan is rated in cfm (cubic feet per minute) of airflow.
A general rule is you need 1.1 cfms for each square foot of bathroom floor area. Dividing the cfm of a fan by its electricity usage (watts) is a good way to compare their efficiencies.
