Basement Plumbing Advice

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New Member
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Central New Jersey
Hi Everyone,

First I want to thank anyone who's taking the time to read this and offer their advice. I'm an over-confident DIYer, probably biting off more than I can chew, but for something like this I want to make sure I'm doing it right. Secondly, want to apologize if any of my plans appears poorly drawn, stupid or ignorant. I feel like I've done ample research, but a few days of Googling and Youtubing is nothing compared to years of experience.

So the plan is to build a bathroom with shower in my basement. I never used a 3d modeling software until I wrote this post, so the pipe fittings ARE NOT ACCURATE in drawing. Assume the pipes are sloped properly (1/4" per foot for waste and vents). Stud placement is not to scale

This is the top view:

Screenshot 2024-01-21 at 11.53.47 PM.png

A few things to note:
- I'm located in NJ.
- The bathroom is 5' wide and roughly 13' in length.
- Due to the location of existing lally columns, ducts, stairs, and other "un-movables", this is the best use of space.
- The sewage pit placement can be moved maybe a few inches.
- The toilet wall is framed with 2"x6"

This is a side-ish view:

Screenshot 2024-01-21 at 11.53.39 PM.png

Back View:

Screenshot 2024-01-21 at 11.54.13 PM.png

Rendered View:

Screenshot 2024-01-22 at 6.01.22 PM.png

Additional Questions:
- Venting:
* True/false, AAV can be used for the ejector? (
* True/false, AAV can be used for the sink + toilet + shower?-
* True/false, the sewage pit vent CANNOT be combined with the sink + toilet + shower vent?
* If it cannot be combined and no AAV, does that mean I need to run TWO 2" pipes from the basement ALL THE WAY to the roof?!
* Can I use a wye for the vent fitting off of the waste pipe? Can't find an exact answer for horizontal venting...

- Main Line:
* For the ejector discharge, starting from the bottom:
- 2" pipe ==>
- check value ==>
- on/off valve ==>
- 90 deg elbow to horizontal, higher than the main line (regular or long sweep?) ==>
- 90 deg elbow to vertical in to ==>
- 4" x 2" x 4" wye (spliced in the main line using 2 x 4" No Hub Coupling)
- Ejector:
* True/false, should be on separate GFCI breaker?

Again, thanks again for reading and advising.


New Member
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New York
Did you ever get answers to this? I have the same questions about aav on fixtures in the basement and if you had to run two separate pipes for the vents with the ejector

Jeff H Young

In the Trades
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Dry vent for shower wont fly under slab toilet vent under slab wont fly either. 2 major issues
Hey, wait a minute.

This is awkward, but...

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