I'm trying to figure out the best way to vent a drain pump I plan on installing. I currently have a one story building with a concrete floor. The bathroom is in one corner of the room, and I'd like to add a sink to the other side of the room. The problem is that there is a doorway and a hall that separates the two areas. This prevents me from tying directly into the existing drain and vent stack. OK, so now I need a drain pump. I can run the new drain line from the pump up and over to the doorway (in the suspended ceiling area) to the existing drain/stack. The question I have is: Do I do the same thing with the vent line, or do I need to try to go straight up through the ceiling and through the roof?