I am finishing my basement and am having trouble on how to run the exhaust fan venting. My bathroom is not near any outside wall. 1 wall is next to the stairs, the other is next to the foundation (and garage), the others are next to the family room & a bedroom.

My first thought is to run the venting inside the floor joists to the back of the house (~25 ft) and then make a 90 degree for ~4 ft and then 90 again to the outside under my deck. Without the 2 90's I would be venting out the upstairs 1 foot overhang.
I live in Minnesota, so I do not want to sacrifice the isolation.

If I went up to the roof I would be looking at ~20ft vertical climb.

The bath is not a primary bath so it would not be used much, but my fear is with the first option I would get water build up inside the pipe. Would this be OK, since it should evaporate?

With the second option I would think that the water would just come back down.

Thanks in advanced.