Help with DWV layout, especially venting

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jk55

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I am getting rid of the cast iron drains from 1924. Please take a look at what I am planning to do and let me know what you think about the venting etc. On the main floor is a small bathroom, a washing machine, and a kitchen sink. Presently all these fixtures are draining through a main, 4" stack, in the basement, which is also a vent for all the fixtures except the kitchen sink which has it's own vent.

The main stack presently is a straight vertical shot from the roof to where it makes a 90 and leaves the foundation in the basement. I need to change where the main stack is exiting the foundation so it can be connected with the new buried outside sewer line.

Once the cast pipes are removed I will be left with the main stack, coming from the roof, entering the basement, and now that will be used as a 4" vent. I will then need to run a new 4" horizontal main house drain to where it will eventually drop down and turn and exit the foundation.

I have flexibility how I can run the old 4" vent pipe once it enters the basement and also how to run all the branches, to connect with the new horizontal 4" main drain, or even connect branches together. I was planning on running all branches from the fixtures with 2" pipe. The main thing I am concerned about is the proper venting. I can't do anything to run new vents in the walls and there is no attic. I would rather not use AAV valves if it can be done without them. It seems like there will be wet venting. I have a few diagrams of different ways I thought to do it. Please let me know if any will work or any improved ways of doing this. thanks.

Diag A seems like I would need to use an AAV valve?
Diag B I moved where the 4" vent connects with 4" main drain.
Diag C moved where WC connects with 4" main drain.
Diag D moved WC to another location where it connects with 4" main drain.
 

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If you are just replacing cast iron with PVC, just replace what they installed. It passed inspection when they installed it and unless there have been any code changes you will be fine
 
If you are just replacing cast iron with PVC, just replace what they installed. It passed inspection when they installed it and unless there have been any code changes you will be fine
plumbing was done in 1924 and some changes have been made to it through the years and I doubt it has been inspected. The reason I am removing the cast is I want it done right and at the same time I need to change the exit point of the house main drain 14 feet horizontally before it exits the basement wall to the new outside sewer
 

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