Basement rough-in from tub to shower

[weir]

The basement rough-in was completed with a shower/tub rough-in. I want to convert it to a shower. I bought an alcove left drain fiberglass tub. The shower does have a p-trap and everything should be vented already. To install the shower drain, do I just need to cut the tub rough-in below the concrete and add two 45 street elbows to where the permanent shower drain will be?

 

[Terry]

You are looking at a vent coming out of the ground is my guess.
There should be a wye, combo or santee down there with a trap arm for the drain. I would dig around and find it.
You will need a p-trap in the ground for the drain. Without the p-trap, you have a direct line to the septic tank odors.

 

[Sponsor]

 

[weir]

Isnt the pipe pictured above for the tub overflow? I was able to dig further and that drain sticking up in connected a ptrap. the ptrap is connected to a wye with the toilet that goes back to sewage pit. that being said, do I just need to cut the pipe sticking up down and elbow out to where the new shower drain is going to be?

 

[Terry]

You should have a vent for that bathroom set. Where is the vent?

The last picture shows a p-trap. The drain can connect to the top of that. Most of us prefer that the trap be under the drain. The more pipe and bends above the trap just means more surface that can build up scum above the water line, and harder to snake.
Since you need to break concrete to relocate the drain, I would at the same time move the p-trap.