I live in a 1 1/2 story home in Houston, Texas. Upstairs is all gameroom. I'd like to add a 1/2 bath. Directly below my planned location is my master bath toilet. Of course, coming up from that toilet is the vent line. I'm no plumber, but I do know that I can't use this line as my waste line from above; at least not with a conventional toilet. So what can I do? I was thinking of running a line down inside the outside wall of my house. Once I reach the first floor, place a sweeping 90 through the outside wall immediately connecting to another sweeping 90 pointing towards the ground. An option here would be a sweeping tee so I could put a clean out here in the vertical. Continuing, I would then run the line underground approximately 25' and tie into my existing line leaving my house running to the sewer main. I hope this makes sense. Am I thinking right or are you laughing so much you'll have a hard time responding? Looking for some help. My house is brick veneer and sitting on a post tension slab. Thanks for the imput.