where should I run the basement bathroom's fan duct to? right now the smarties that built the house put a fan in but it is NOT ducted at all..... just blows the air into the ceiling.... on the closest wall there is the deck attached to the rim joist... on the next closest wall (about 19 ft away) is where all the service entrance stuff is and AC compressor line entrance... funace combustion venting etc.... should I run it all the way there or is there anyther way to do this? also what is the best duct to use for this? flex? rigid? metal or Plastic?