Venting Question

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Jun 27, 2020
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Remodeling a single wide mobile home bath, so I know I am already in the weeds
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We are putting in a shower pan and I have a couple of questions regarding the shower drain and vent.?

As you can see in the image the 2" vertical vent runs along the wall and exits up behind the old tub shower plumbing, I can to do a touch of rerouting there so it comes up through the wall instead of up the floor but basically will be same as original, the old tub drain went into this pipe above the floor with a trap.

It is about 3 feet from where the vent goes vertical until it hits the main.

The new shower pan drain is a center drain, and I will be running it over and connecting to the main as indicated, about 4 feet of line.

First Question. Am I good just running my shower drain to the main, or do I also need to put a sanitary T in and branch over to the vent before getting to the main? I guess the question is will I have enough vent from the main where it is connecting or do I need to get to the hook to the vent closer to the drain.

Second Question, as noted in the image there is a steel beam (remember its a mobile home) running under the studs fairly close to where the drain needs to go, and very well may interfere with the P-trap, can I bring the drain over the beam about 18" (I know slope would still have to be correct, then have my Ptrap on another side of the beam so it won't interfere?

Floor joist are 2x6, and sitting on the beam, so not a ton of room to work with above the beam. View attachment 24649