2nd floor bath in old house

Greetings

I am attempting my first bathroom build, in my old farmhouse. I am concerned about any potential sewage problems. Here is what I have so far. Thank you for your time.

 

#1, You did get a permit for this work, right?
Is an AAV even allowed by code in your area>
Is that shower drain 2"?
First thing I see is you've notched the joist instead of drilling holes through them, huge mistake!
You have now weak the whole floor.
May just be the picture angle but that closet flange looks like it's going to be higher then the finished flooring.
Not sure why you used a tee under that flange instead of an elbow unless that's going to be the drain for the sink.

 

Welcome to the forums! I am a carpenter, not a plumber, so we'll wait on the pros in that field. I will, however, chime in on my specialty. You cut joists. What are your plans to keep the floor at those points from failing? You need to install blocking along side the pipes on each side to tie them to each other in order to minimize bowing of the joists. You are running a 2" line to the shower, right? It looks as if you have necked it down to 1 1/2", which will not work.

 

Didn't get a permit. Now I'm wading through county zoning ordinance (thank goodness for PDF), to determine if I'm zoned to require a permit.

I didn't notice that at first! My wife did that part. It will be redone.

The notches were created in the joists when the plumbing was originally placed 70 some years ago. I'm not terribly worried, since there is a box construction directly below that big cut where the soil stack is. That shape goes to the floor of the first floor, and then directly supported beneath with a house jack in the basement. Additional cross-bracing has been added as well.

You are correct. The minimum slope of 1/4" per foot just barely works with the current setup. This raises the height of the toilet about an inch above floor height. To fix that issue I had planned to make a dais for my throne, but I think a closet bend will be much shorter and fit the bill ...

Yes that was the original idea, but nearly every picture and diagram I've seen of bathrooms has the toilet farthest upstream. I may be able to sneak the sink drain alongside, teeing in downstream of the commode. That's why the sanitary 2" to 4" tee is sitting by itself in the picture.

 

The joists were cut 70 years ago when the plumbing was originally installed. I'm not particularly happy about it.
There is a boxed in section beneath that soil stack, going all the way to the first floor floor. Beneath that there is a house jack in the basement. There are cross-braces I put in place and can brace more.

Thank you. I wasn't sure of the best practice here.

I didn't notice that at first, thank you. My wife did that part. It will be redone.

 

A closet bend is the correct fitting to use too. Tees (and Sanitary Tees) aren't allowed to be used on their back like that.