The drain for the shower Im installing sits almost directly above the 3 in main,what is the best way to trap it.Can the wye sit vertical and the trap go beside the waste line a little above it like an s trap or do I put it horizontal and the trap go below the waste line.It's concrete slab

You speak of traps but not one word about a vent. You may not connect to the main without first running a shower vent. You can get past this by connecting the trapped shower vent to the lavatory drain where it will be wet vented. Good luck, Tom

Here is a diagram 4267

Here is the original post https://www.askmehelpdesk.com/plumbing/tying-into-waste-line-under-slab-116509.html

Seems like my questions never get followed through,here is a link to a link for original post please advise me on how to proceed https://www.askmehelpdesk.com/plumbing/hooking-drain-trap-horizontal-123067.html

OK, On the original post I asked for the lavatory to be drawn in so I could wet vent your shower. The problem is that the lavs have a "S" trap and aren't vented correctly. If the old toilet's removed and the only thing draining past the shower is the lavatory then if the lavs drain OK the shower should be vented and drain with no problems. Come off the three inch with a wye,(not a upright wye) or combination wye and eighth bend and bend that around to the "P"trap. The inspector may not approve but it should drain with no problems. Sorry I haven't been posting as much as I usually do. I have had company down from up North the last two months and she takes up a lot of my time. Rrgards, tom

Thank you very much for a quick reply,didn't mean to pressure but wife is getting quite voicey about the holes in the master bath floor

This is the message:

I can't get a full answer to this question in the forum,maybe I'm not doing
Something right.I posted original on 08-07-07. You ask me for more info,I posted
It in the forum but I guess it got too many pages back.Anyway here is the
Original post .thanks
https://www.askmehelpdesk.com/plumbing/hooking-drain-trap-horizontal-123067.html

What type of a "full answer" are you seeking? Without being there we can't give you fitting by fitting, joint by joint instruction. I couldn't answer you until you drew in the lavatory. Now that you've showed me the total set up you have my answeri my last post. What more do you wish to know? Regards, Tom

I was not asking fitting by fitting instructions.I just wanted to know if the vent would work.You ask me to draw the lavatory in Aug,5th and I did.Ireposted Aug 8th still no answer.This last post Aug 27 with links you read all the post and answered my question.I'm sure my post got washed under the bridge with the dozen of other post you answer everyday and I do appreciate that you take the time to help all of us that you give amazingly accurate advice.thats why I cliked on support this member and sent a thank you. Thanks again JH

I was not asking fitting by fitting instructions.I just wanted to know if the vent would work.You ask me to draw the lavatory in Aug,5th and i did.Ireposted Aug 8th still no answer.This last post Aug 27 with links you read all the post and answered my question.I'm sure my post got washed under the bridge with the dozen of other post you answer everyday and I do appreciate that you take the time to help all of us that you give amazingly accurate advice.thats why I cliked on support this member and sent a thank you. Thanks again JH
I guess you missed this in my earlier post. " the shower should be vented and drain with no problems." The existing vent should service the group. It may not pass code but should give no problems with the possible exception of that "S" trap followed by a long run to the vent. Grease and hair build up in bathroom drains, If you have the room I would install a cleanout in the cabinet. Good luck, Tom

Actually that e-mail was sent before you answered me in the forum,even before my last post,sorry for the misunderstanding.anyway I'm closing that long run and ran a new vent behind the new toilet to revent in the attic.with a drain line from the lav.to there.Hopefully that will work better,thanks jh