How to Use an Inline Exhaust Fan to Vent More Than One Bathroom First, install plastic exhaust grills in each bathroom ceiling. Run 4-in. flexible ductwork from the grills to the inline fan.

Bathroom exhaust fans are designed to fit a particular ... While it may seem logical that a fan running at a higher speed trumps a fan at a lower speed, you might not see that big a difference ...

It is not uncommon to see a variable-speed fan in the second ventilation stage while the first-stage fan is running at full speed. This scenario should be avoided. One fan controller that implements ...