Bathroom vent fans
GBA Editor
| Posted in Mechanicals on
I have two questions regarding bathroom vent fans.
1) I just discovered that the bathroom fans in my parents’ house is vented to the attic and not to the outside. How important is it that this be fixed?
2) The house that I’m currently living in has a window in the bathroom but no vent fan. There looks to be some mold on the ceiling. What is the best solution to this? Would running a standing fan in the bathroom right after a shower help to evaporate the water more quickly?
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Replies
Karen,
1. Every bathroom fan should be vented to the exterior, not to the attic. Whether or not this is extremely important or just plain important depends, in part, on the condition of the underside of the roof sheathing and the condition of the rafters in your attic. If there are signs of frost, condensation, or mold on the underside of your roof sheathing or your rafters, correcting this venting problem should be a top priority.
2. The best solution to a bathroom without an exhaust fan is to install an exhaust fan properly vented to the exterior.
Here's more information on exhaust fans:
https://www.greenbuildingadvisor.com/green-basics/exhaust-ventilation