Bathroom Fan Condensation

This is the first thing you have to check.

Whole house fan noise level. If bath fan ducting isnt properly insulated the moist air from your house will condense inside the duct. You may notice water dripping during or shortly after taking a shower. The usual cause is condensation inside the duct.

Condensation in the duct. What are the options for bathroom exhaust fans. In summary the only meaningful way i found to deal with bathroom condensation especially if you live in an old house or a house with uninsulated or cold walls is to try and contain the water vapour and then use a good quality extractor fan ideally a humidity sensing one to take that water vapour out of the room efficiently.

A bathroom fan should exhaust warm moist air through sealed insulated ducts so that walls and ceilings are not exposed to condensation or leaked moisture. The first step is to head to the attic. Then it runs back down the duct to drip out of the fan into the room.

Water stains on the ceiling around your bath fan may indicate a leak coming from the vent cap on your roof but condensation is the more likely culprit. With insulation condensation will occur much higher up but it will happen. As soon as it hits a surface colder than dew point condensation happens.

Many people notice the issue when the bathroom exhaust fan starts dripping on their head as they step out after a shower. You may find dripping water during or shortly after a shower. Bathroom exhaust has a very high dew point.

The only solution is to not vent straight up. The problem might be the condensation in the cold duct. In most of the dripping water from the bathroom fan cases this is the main culprit that you have to consider first.