Slab on grade DWV retrofit

[Bobby40]

Hello all. I have undertaken a difficult job (for me), replacing my homes entire cast iron dwv system with pvc. I am attempting to do this myself and at this point have the first bathroom roughed in. I am ready to back fill but want to have someone check my work before it gets buried. It is a horizontal wet vented system serving 2 lav sinks , 1 shower and 1 water closet. All horizontal pipe runs are at 1/4" per foot drop. The shower arm is in 2", the lavs//vent are in 3" and water closet is in 4".
My chief concerns are:
1. The shower trap arm measures 67" in developed length. I have seen codes that state 60"and 96" are maximum lengths. (different plumbing codes)
2. The shower tailpiece will probably end up at 20" in length (vertical) from the drain to the p trap weir. I believe this meets code but seems a bit long to me.
3. The shower trap arm has 2 horizontal 45 degree turns which should not be a problem but I would prefer not to have them in the pipe run.
Are any of these concerns valid?
Please see the attached photos and comment if you see anything concerning. Many thanks!

 

[Twowaxhack]

Draw the complete piping install on paper and post a pic.

 

[MicEd69]

Like Twowaxhack said, a complete picture is required to provide you with any reasonable reply.

 

[Bobby40]

Here is a drawing. I added a vent to the shower arm and removed those 45 bends to come straight into the 4".

 

[MicEd69]

I think you are under the IPC, or a derivative thereof. As such. you are probably OK with the venting you show for the toilet. But if you are under UPC or some local additions to the IPC, you may need to vent your toilet differently. You don't show your kitchen sink, so I'm not sure if that venting will help if there is an issue with your toilet venting.

It's a little unclear what is going on at the connection of the shower vent to the fitting group that is shown above the "vertical stack" on your sketch. Is there a separate vent for the top sink on your sketch, or do both sinks drain into the "vertical stack" through a 3x3x2x2 double Sanitary tee?
I'm also wondering why you used a capped 4x4x2 wye for the shower entry into the 4" drain line instead of a 2" 45 and a reducer. I guess it is fine, I just don't like dead end piping that never gets flushed out.

The fitting choice for the shower vent to the drain also needs to be considered. Some inspectors and plumbers interpret that a dry vent connection to a horizontal drain needs to be a wye and 1/8 bend or combo, while some agree that a Sanitary tee on its back is acceptable. A wye and 1/8 bend or combo does provide a much better path for snaking in case of a blockage. The other dry vent fittings are also relatively important for function and future possible maintenance. So, we still need more information to provide you with a better review.

 

[Rossando]

Not bad my man, definitely should put a clean out at the end of the line of the main. 4' for the length of run for the shower trap/weir to vent connection. Meanwhile that vent connection should be rolled up a bit at the wye. Puttana cleanout on the vent you will need it