They meet the ASHRAE 62.2 requirements, which outlines the requirements for ventilation to ensure acceptable indoor air quality.
They run super quietly, can be set to turn on automatically, and cost practically nothing to run. I have a hard time remembering to turn on the fan before I get in the shower, which causes mold and paint damage, so that feature is fantastic for people who forget. Also, since it runs continuously on a lower speed, it will pick up any toilet smells. You know, those smells.
My favorite Delta BreezGreenBuilder fan is the BGr80H-
- 0.8 Sones
- 80 CFM
- Humidity sensor that can be set to turn the fan on between 50% and 80% humidity
- Adjustable low speed
- Annual cost for running continuously is $10.20/year
This fan costs only $88.95, and can easily be installed with the included guide.
The fan will replace Broan models 688, 670, 671, 675, 695, and 696N, so no adjustments to the current hole or venting would need to be made.