I am planning on adding a bath and need to know how far away from the main stack can I place the toilet. The plan is about 9 ft away. I have enough room for the 1/4″ per foot, but is 9ft too far. Also, will I need to add a separate vent close to the new toilet so that the new toilet flushes correctly. Second, for the sink/shower drains: Can I tie in to a washing machine drain directly under the new bathroom. The washing machine has a trap on it and I would tie into the drain line after the trap (downhill).
Even if your code says 6′ are more I would put a 2″ vent on the toilet. If your washing machine drain has a vent on it connect below the tee, if it has no vent then vent it and connect below tee, best is to check your local code.