Can the toilet wye 45 be connected at the top (90 degrees) in a wet vented bathroom?

[jbradley2093]

The code diagrams show the wye connections directly on the side, however this will not work for my needs. The photo shows the toilet drain and represents what I'm talking about.


This is a diy (permitted) bathroom install in an old house. I appreciate your time and input, it's greatly appreciated. My area uses the Michigan 2015 code.

Thank you

**I have found answers myself to the other questions I had in this post originally**


**

 

[Breplum]

Shower trap is definitely NO. If you are trying to do horizontal wet venting, read all the pertinent code, look at all the images online. Best to have a plumber at least consult for all your issues. There is way more to know than we can teach you online in a few posts. There are so many ways to go wrong and so many mistakes to make.
Your inspector is not going to teach you either...and they often have poor training.

 

[Sponsor]

 

[jbradley2093]

Shower trap is definitely NO. If you are trying to do horizontal wet venting, read all the pertinent code, look at all the images online. Best to have a plumber at least consult for all your issues. There is way more to know than we can teach you online in a few posts. There are so many ways to go wrong and so many mistakes to make.
Your inspector is not going to teach you either...and they often have poor training.

Thank you for the response. Unfortunately I cannot find a plumber willing to consult for a fee - I have an HVAC guy and Electrician doing so, but have struck out with plumbers.

I NOW know the vent connection itself must enter below 45 degrees. I also I know what I did wrong for the shower and that's an easy fix, but the toilet connection is not an easy fix if that connection is unacceptable.

 

[Tuttles Revenge]

Do you have a Link to the IRC code that is in effect in your area?

Generally speaking and without understanding how the IRC views things: horizontal wet venting relies on the principle that all fixtures that are being vented by that horizontal run, enter it and remain horizontal. Other bathroom fixtures can enter it above the invert, but they must have their own individual vent.

 

[wwhitney]

This question is an annoying inconsistency between the IRC and the IPC.

The IPC does not prohibit that arrangement for a WC (since it is not subject to the trap weir rule).

Chapter 9 Vents: Vents, 2018 Michigan Plumbing Code | UpCodes

UpCodes offers a consolidated resource of construction and building code grouped by jurisdiction

up.codes

But the IRC added the sentence "Each fixture drain shall connect horizontally to the horizontal branch being wet vented or shall have a dry vent."

Chapter 31 Vents: Vents, Michigan Residential Code 2015 | UpCodes

UpCodes offers a consolidated resource of construction and building code grouped by jurisdiction

up.codes

Since Michigan has adopted Chapter 31 of the IRC (at least according to up.codes), the OP needs to read the Chapter 1 scoping sections of the two Michigan adopted codes and determine if they have the option to do the install under the IPC, or if they must comply with the IRC. That choice, if available, may have other ramifications.

Cheers, Wayne

 

[jbradley2093]

I just thought I would update and say that here is the final mock up and it was just approved by the inspector. I noted the IPC with respect to the toilet connection and he was fine with it. He didn't seem to care so much about the text of the code as much as if the setup would work properly .

Thank you all who took the time to help me. I appreciate it greatly.

 

[Jeff H Young]

Id cut it all out back to 2 inches sticking out the 3 inch wye and jump up in height with 2 45s or even 22s and then continue similar but with a2 inch drain after the wye going to lav continuing to the tubas a 3 inch trap arm is not a good idea or needed.
Pretty easy but sorry you gotta tear it out