underground pipe layout

This is my first attempt ever at installing underground pipes for a full bath in the basement and i don’t think it was done properly, but i’d like to know if:

  1. Is the shower (far right 2" pipe) properly vented? Am i correct to assume that the shower is properly vented because the sink drain is between the toilet and the shower?

  2. If the shower trap looks good? Or did i create an s-trap?

  3. When I pour the 4" of concrete in the shower area to close it, whats the best way to do it? the concern is that the majority of the trap would be concreted and enveloped in that area. is this method okay or is there an alternative way?

So from left to right it is sink, toilet, and shower. the sink will drain into the main stack. the main stack then goes down under the concrete and sweeps to the right and connects to the 3" toilet drain approx 1 foot to the right of where toilet flange would be. This would vent the toilet and the shower. The toilet drain then continues to the right and then the shower p trap appears and drains into the 3" drain that originates from the toilet drain. The distance from the shower drain to what I presume is the vent is approx 4 feet. The graph paper diagram shows it better.

Thanks in advance.

more pics

Sorry to say this, but you need some professional help. This is wrong in many ways. I’ll draw up a typical and post it for you.

This guy was on another site yesterday, and was told that it was screwed up by many plumbing professionals. I guess he wants to find somebody to pat him on the back and tell him he did a good job, even though it’s got a sore lack of proper venting, an improperly used tee, and an improper shower s-trap.

Here is a typical for my area. This is not necessarily the right way for your area. Talk to a local plumber.

Typical Plbg for single bath.jpg

Oh well, thanks Marc.

thanks jack, that does make sense.

the issue i had with my drawing was that i needed to move my shower approximately 22" to the right and i just extended the piece over leaving everything the way it was. didn’t want a pat on the back, just confirmation.

just from reading and thinking about it, i didn’t think the original way was correct, so thats why i posted and asked and i do appreciate your help.

the response from contractorstalk was denigrating, but at the same time what they were telling me was that the plumber that did the underground work during the construction was incorrect. i only moved the piece over about 2 feet.