Adding venting to an unvented downstairs bathroom
Hi, this is my first post here and I appreciate any help you can give me with a plumbing project I have to figure out in my new old house. When we bought this 1890's house three years ago, it had a downstairs kitchen and half bath and a full upstairs bathroom. I remodeled the kitchen in July 2005, and then started to notice that the new kitchen sink gurgled whenever the upstairs toilet was flushed. The old sink didn't do that, or maybe it did and I just didn't notice? Anyway, for some reason I gave myself license to put it in the back of my mind as something I would think about later. :rolleyes:
Now the upstairs bathroom tile has rotted out and I HAVE to put a full bathroom plus a washer and dryer in the downstairs bathroom before I can start working on fixing the upstairs. Here's the problem--the downstairs bathroom is clearly not vented, and there's no way to tap into the existing soil stack above the upstairs bathroom fixtures to vent the downstairs. Once I have four or five people in full-time use of a full bathroom downstairs, I am afraid my plumbing problems are going to multiply quickly.
What do I do? :confused:
Can I put vents inside the walls, or won't they just flood/overflow if my drain ever backs up? Can I run a 2" PVC vent from the soil stack in the basement out through a side wall of the house and up the side of the roof, using a couple of 90's to get past the roof ridge? Or does the tub/shower, sink, and clothes washer each have to be vented above their individual drains in order for it to work right?
Thanks in advance for any help or guidance you can give me!