I am renovating my house and I want to add a new bathroom up stairs at the opposite end of the house from the main stack. The distance would be 25-30 feet away. The drain would run about 8 feet across on proper slope, then on a 45 degree angle down for about 10 feet and then again horizontally for about 10 feet to the main stack. My first opinion would be this is to far for a drain to run. If everything was vented properly would this work? There would also be a sink and shower attached to this drain, which would add water flow to keep the drain clear.
Thanks
Brody

Hey Brody,
The lavatory roof vent will wet vent both the toilet and the shower. I'm assuming the shower will be draining into the lavatory drain where it will be wet vented. If not then a dedicated vent must be taken off the shower. Your toilet will be just fine just as long as the lavatory drain ties into the toilet branch within 10 feet or less. Good luck, Tom