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Insulating bathroom fan duct

When installing a bathroom vent fan duct through an uninsulated attic should the vent duct be insulated to prevent or reduce condensation? It is about a 6 foot run of duct. We live in West Virginia where the winters can be quite cold.

Timothy Miller
Re: Insulating bathroom fan duct

Howdy surely the attic has some insulation???????

So you can wrap the pipe with fiberglass . The fan should have a flap door designed to stop back drafting. Be sure to exhaust the air out of the dwelling not just into the attic.

Re: Insulating bathroom fan duct


The attic does have insulation, guess I should have said "unheated" instead of uninsulated!

Thanks for the response Timothy, much appreciated!


Re: Insulating bathroom fan duct

You could use flex duct which can be bought at your local Home Store, Lowes , Home Depot, etc. and yes it should be insulated to stop condensation and mold

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