Fixing Bathroom Ventilation

Mold and mildew growing on the bathroom ceilings was all the evidence needed that the ventilation fans were not working effectively.

Mold and mildew growing on the bathroom ceilings was all the evidence needed that the ventilation fans were not working effectively.

The oblong stain on the ceiling of the shared bath was curious.

The author checked the airflow of the two fans using a duct hood and a manometer. He found that the fans were working at only about 60 percent of their rated 70-cfm capacity.

Fiberglass insulation, because it had been loosely laid over the bath fans, did not contact the drywall. Not only did this insulate poorly, but it allowed cold winter air to reach the ceiling board.

The ductwork, the wiring, and the fan itself made the area difficult to insulate properly.

Join the Discussion

Please read our Content Guidelines before posting

Close X