Another Bathroom is needed... The boys are fighting to use the bathroom
First, thank you for having this kind of forum. Now also let me say that I'm not well versed in the plumbing lingo so hopefully you will be patient with my questions.
I live in a 3 levels home (Basement, Main, Upstairs) with the existing bathroom is on the main floor. I'm planing to add another stack/vent 4" pipe,which will be roughed in with the existing stack/vent in the basement to the roof. This new stack/vent will serve a new bathroom from upstairs, not the main floor, and the half bath down in the basement.
1. Would this new stack/vent be sufficiently served all the fixtures of a new bathroom, and a new half bath, in addition of reconfigure of laundry washer?
2. I'm trying to figure out how I would run the vents for the toilet, lavatory, and the laundry washer in the basement. The way I read the code, If I stay within the "critical distance" I can drain everything into this new stack/vent without vents for the toilet, lav, and laundry washer? All of these fixtures are within 3 feet of the new stack/vent here.
3. If we need to have the vents for the toilet, lav, and laundry in the basement, I'm thinking of running a 2" vent pipe parallel with stack/vent up pass the bathroom upstairs and connect it back to this new stack/vent. What's the size of the vent pipe would you recommend? By running the vent pipe parallel with the stack/vent pipe, how far away does the vent pipe needs to be apart from the new stack/vent?
4. For the new bathroom upstairs, I'm planning to use a 3" drain pipe for the toilet. The tub and lavatory will have 2" drain pipes. I will group all these fixtures of this new bathroom together with a 2" vent pipe. What is your recommendation here?
5. Would it also be OK to group the 2" vent pipe of all the fixtures in the basement with the 2" vent pipe of the new bathroom upstairs together and tie it in with the new stack/vent pipe?
I understand venting is just as important as draining, any suggestions for what I'd like to achieve would greatly appreciated. I'd to know the answers before we invest huge amount of money into the project or sale the home and get another place.
-Thanks
Vince in Portland Oregon