Bathroom Exhaust Vent – Aluminum or Plastic Vent Pipe
On a bathroom exhaust vent. Is it better to use an insulated plastic flexible exhaust or a flexible aluminum vent pipe? Will an aluminum vent pipe cause more condensation issues in the winter since the metal pipe will be colder than a plastic flex line, causing the warm moist air to hit the cold outside air and condense?
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Replies
I would go with the insulated metal duct as it is likely to hold up better over time. I have found the flexible plastic stuff to often be so thin that I expect it will eventually crack and tear. Note that you're better off using rigid ducting as much as possible too, since it has less resistance to airflow and will help your fan perform better. Ideally you want as short, and as straight, a run as possible.
Bill
Thanks for the info! I ordered up some rigid metal flex duct and will run an insulating sleeve on it. The ducting run is very short (under 10'). I will also have a flapper door on the exterior vent which will help keep the cold air out.