We want to put a full or 3/4 bathroom in my daughter's bedroom, which is over the garage. One contractor suggested locating the new bathroom so that it would share a wall with the downstairs half bath and use the same piping. However, this placement would allow only a very small, narrow half bath. We would like to locate it at the other end of the room, which is upstairs and across a stairway from the laundry room. We could run piping, etc., through a crawl space that is over the stairway and laundry room. My questions: Is this feasible? Would we run into any contamination, odor, etc. of the washing machine? Would we need to replumb the washer lines? Any other thoughts? Thanks for any help--I am a total novice, though my husband has some limited plumbing experience.