Bathroom exhaust duct
E247
| Posted in General Questions on
I have a conditioned attic and I wanted to know if the bathroom exhaust ducts need to be insulated. There’s a backdraft damper on the roof termination and at one built into the fan.
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Replies
E247,
First of all, can you tell use your name? (I'm Martin.)
Q. "I have a conditioned attic and I wanted to know if the bathroom exhaust ducts need to be insulated."
A. The answer depends on your climate zone. If you've got a very short duct run that passes through roof insulation and ends in a roof termination, your duct is obviously already insulated.
For more information, see "Bathroom Exhaust Fans."
Climate Zone 2A. One run is about 6' from the fan to the roof termination and the other is about 20' from the bath fan to the roof termination. There is spray foam against the roof deck so most of the duct isn't insulated.
E247,
If the 6-foot length of duct is in conditioned space -- and it sounds like it is -- then the duct doesn't need to be insulated.