Does a bathroom exhaust fan have to be

[rusty quoin]

5. Never into the attic.

If you get it to the attic, you are mostly there. Find a reasonably priced guy who does roof work to remove a few shingles, cut a round hole and install a vent on the roof and flash around it, and all you'll need to do is connect to the roof vent to the bathroom exhaust motor unit ...never vent moist things like dryers to crawl spaces or bathrooms to attics.

You can also vent a bathroom to an exterior wall. It requires no ducting and if your bath has such a wall, it's the shortest, hence the most efficient. Think about the easiest to wire method also, and which way looks better on the exterior of the house.