DIYer in a 1917 house. I'm adding a bigger tub...I added subfloor back in under the tub and sistered the murdered joist and this is the best configuration I came up with. It's a huge upgrade from what was there, but before I glue it, do you all see any problems I might have?

She’s a beaut Clark.
Always best to avoid an L.A. trap (union) in a concealed location.
There's a drop ceiling below it but I planned to glue it shut because it's a Sunday afternoon and I live in nowhere 😭
If that's all dry fit, you'll need longer pieces for when you glue them.
Why's that?
Unless all these pieces are slammed all the way in, the glue acts like a lubricant and everything will seat further in once it's glued.
They're all jammed together really good but that's good info I hadn't thought about
Meh, it'll ride.
Just mark the pipe right where it meets the hub and double check when you pull it apart that its the depth of the hub.
It will ride for the first few, then take a break and check your measurements. Most of the time you can dry fit a couple sub assemblies and the cut the pieces that tie those together for length. Order of operations is different for each job but often one the most important things to consider. I’ve definitely piped myself into a corner before
Expect it to be off
Take a marker and mark everything.
A red one
Aaaalso, the glue will make them creep back out, so don’t use too much glue, and give it a few seconds before moving on, or everything will be pushing apart
Strange how you say it’s Sunday and live in nowhere. I know it were me I’d wait one additional day just in case things go wrong. Why waste multi more hours trying to correct a Gerry rid when it could have been the 1st time around.
Why are you calling it an L.A trap? What is the backstory
It’s what I’ve grown up with from way back.
L.A. traps, Milwaukee traps, New York traps. Different terms that’s all.
Could mean multiple things if you catch my drift ;)
L.A. traps usually feature a compression joint that allows for angle adjustments during installation, while New York traps typically do not have this feature and go straight into the wall. NY traps are often not allowed by code anymore because they can siphon dry, but they're usually shorter so if there's not enough clearance you'll see them used as a cheater. I'm guilty of that in a Sisyphean inheritance reno because doing it to code would have required an immense amount of additional work and it was my own place, but I was meticulous about the venting.
Damn, good spot on the union...
That cut joist is holding most of the tub weight. While the hole does look to be within spec I would add a metal bracket to reenforce it.
when marking pipe with sharpie, the line needs to be longer. when you apply solvent weld glue on the outside of the pipe, those little red dots will be eaten away
Remove the elbow between the tee and the drain shoe. There is no reason for it.
Without cutting the base of the tub I can't turn the shoe far enough to run straight into the San tee
Can you switch to a 45?
The tee is too close to the shoe for a 45 to work either
Did you try a st 45
I didn't. I don't have one on hand and it's Sunday afternoon
If you have a long sweep 90, that would be better.
Use a glue trap but it’s fine. On older homes a lot of times things were different so code doesn’t always apply in the regular sense. With the 2 inch goes into the 3 inch pipe as long as it’s flat it’ll still act like a vent aka a flat vent. It’s not code per say but it works great.
My code is YES as long as upstream of the wye is a wet vent (sink)
There is
Your good. The only thing I would do differently is remove the 90. Other than that 100% good job!
Thank you! I'd have to cut the support base of the tub to be able to line up the waste shoe with the tee
That 90 is not to code in most cases but will drain. Tough to snake if needed in the future. Sounds like you are on a time frame and need to finish today, if you can wait, change the p-trap to solvent weld unless you’re not concerned with code. I know you said you were going to glue it. Overall it will work. Enjoy your new tub.
Usually snaking through the overflow anyway
you don't need that 90 turning into the ty. point the 90 under the tub directly at ty and save 90°
It’ll work.
Add a air intake vent?
Is this line vented after the tub?
Plumbing for 40 years! That’s tight quarters and not much room for any other scenario. I’d also avoid the la trap, but drop ceiling works. Nice work, live with it.
Instead of the 90° on the horizontal can't you go straight in?
Looks great, good job.
Send it bud. Zip it and ship it.
Is that an s-trap below? If it is, needs to fixed.
Looks fine
I would try to turn the t why and drain to hit it straight or turn enough to use a 45. I don't like the 90. Also use a solid ptrap.
Where is the vent for the tub? Its probably not in the picture but just wondering
What’s upstream of the wye?
I would angle the tub shoe toward the tee to eliminate the 90 .(if theres room)
Send it
You could have pointed the tee straight at the shoe.
Jeeze- shark bites- micro, primer……
Not bad…
No shot you can snake this when it clogs. Should be a straight drop from the overflow with the trap below.
You would likely need to head off the joist and properly structure to make room for the trap in the correct position. More work for sure due to the unfortunate location of that joist.
Will this work? Yes. Is it serviceable? No.
but the trap is below the wastepipe, wont that resrict tub drain , is that going to vent or is another sink behind?
No 90⁰ on its side, turn the TWYE and tub drain
looks good. could have done a straight shot from the tub drain to the tee and got rid of the 90 unless theres something i cant see where the 90 is helping it get by.
https://preview.redd.it/bei0k4t01o7g1.jpeg?width=3472&format=pjpg&auto=webp&s=770970b11dac09790a08946bb0a5ce408d934c04
I'm back to show the finished product. I was able to get the 90 down to a 45 without cutting the tub or too much more subfloor and I put in a glue up trap. It drains, flows and doesn't leak, gurgle or syphon so it's a win for me. I'm sure it'll outlast the crappy tub 😂
So thank you to everyone that offered solid advice! Much appreciated!
Just curious where is the vent pipe in relation to the tub and pictured plumbing... or is this going drain very slow and go glug glug glug?