I am wanting to put in a second floor bathroom that is about 20 feet from the stack. There are a couple of problems. First, the waste pipe would run perpendicular to the floor joints and that means a lot of holes- worried about structural integrity of the joints. Second, even if I got to the stack, the inlet there would be too high in relation to the height of the drains, accounting for the necessary slope of the drain pipe, which would have to drop about five inches from the drain to the stack. Here's my question: Can I put a three or four inch drain pipe straight down into the basement, from the bathroom, then slope the pipe over to the stack? It would work logistically but would it be permissible with regard to codes? I could vent out the roof, right at the bathroom, I think. Thanks for your help.