I have a bathroom exhaust fan that is vented into the attic, up to the ridge-vent area. Since the weather had gotten colder, water drips back into the bathroom from the fan after it has been on for a while. Do I need a certain type of material for the vent? Should I insulate it? I’m not sure what the solution is. Thanks for your help.
The duct should be insulated. Make as short of a run as possible to a vent connector through the roof deck. The fan duct should not be run to the ridge-vent. You can find insulated duct and a vent connectors at a building supply store.
The fan and the vent connector through the roof should also have a damper that closes when the fan is off to limit air movement.