The waste stack for the toilet/sink in the attic is the best.

Do not use the accordion style vent pipe as the accordion will allow moisture to condense in it.

Use something like abs or pvc pipe of an inside diameter sufficient to allow coupling to the fan vent.

Run the pipe from the fan outlet to the toilet vent stack and join the two pipes via a mechanical sleeve.

If the bath has an outside wall and you cannot get to the attic, a direct vent on the outside wall works.

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PDQ

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"JA" wrote in message ...
| Would anyone like to weigh in on where I should vent a bathroom fan? (Not
| the attic--I know that!) I've found that some home repair sites say it's OK
| or preferred to vent through the soffit; others say this is nearly as bad as
| venting into the attic and that one should vent through the roof; and yet
| others say to avoid the roof and go through the soffit or gable end of the
| house.
|
| Does this all depend on where you live? For instance, in areas with heavy
| snow, the roof vent could get blocked and therefore venting through the
| soffit would be preferred, but everywhere else the roof is the way to go?
| Is it really bad to vent through the soffit?
|
|