I need some advice on venting/. It would be very difficult for me to run a vent line except in one place where I can get it up to the roof and out. I'd like to use "Y" connections as in the diagram to hook up a vent system. It's all for a 1st floor set up and the only way waste is going out of the house is via a horizintal run in the basement. I wonder how far away can the sink be in this set up. The toilet will be about 8" from the vent pipe thanks!