The spaces between the basement ceiling joists (not all of them) is packed with pipes. The ones that are free would allow to run PVC pipe, but the pipe would exit the building less than 3 feet away from windows / patio doors. I was told it's a code violation.
You might double check with the AHJ regarding that code. The install diagrams that I've seen (example, page 30) seem to indicate that it's only 12" from the edge of the opening. Maybe local code is more strict than national ones.
