Thanks to everyone for the great advice! While I suspect I'll be coming back with more questions, I'll certainly be going into this project with a lot more confidence. Cheers!

 

The easiest way to do this is to glue up the trap and waste and overflow before the final tub set. This way, nothing is glued blindly. No need to slit or sand pipe. A couple dry fits and pencil marks for reference should do it.
When all is glued, set the tub in place and screw in the drain and attach the overflow nut. The trick is getting the gaskets in position- a little tacky adhesive helps here....

 

Since you have no access, you have to options- go ahead and make an access and loosen the trap nut. Or, working from above, remove the strainer from the tub shoe and remove the overflow cover plate.
Both methods will allow you to remove the tub without removing the trap.
Once you get the new tub, you can test fit it to the old trap and see what adjustments to make.

 

Since you have no access, you have to options- go ahead and make an access and loosen the trap nut. Or, working from above, remove the strainer from the tub shoe and remove the overflow cover plate.
Both methods will allow you to remove the tub without removing the trap.
Once you get the new tub, you can test fit it to the old trap and see what adjustments to make.

Thanks for your reply... Yeah, I'm definitely going to disconnect the plumbing from the tub--creating access from underneath would be a highly undesirable option! What I'm curious about, though, is how a professional would handle this if the plumbing does NOT line up... Are there any viable options other than removing more of the floor and replacing the whole section that's in the picture? (If I'm getting ahead of myself, let me know... I just trying to plan ahead :smile

 

.... assuming aesthetics/etc allow, and considering your impared/non-access to the DWV,(and maybe supply), you may want to specifically purchase your new tub dependent on it's drainage specs... ie...plan ahead.

 

Makes sense, but the thing is, there's a specific make/model tub that my wife wants to get. In doing some rough measurements, it looks like the new tub will be close, but may be about an inch or so away from the existing drain. Was my thought to replace the existing trap and section of pipe not a good idea?

 

There is a method to hook up the tub without access holes, but it takes some precise measuring and test fitting the tub.
If you are working with only an inch difference, I think it's doable. An access from the end wall might help
A couple years ago we (2 men) would set 2nd floor neo angle tubs in mortar base about once a week. We got it down to about 3 hrs. This included the wide spread deck faucet too- no ceiling or wall access

 

There is a method to hook up the tub without access holes, but it takes some precise measuring and test fitting the tub.

Yes, I saw some videos of this being done... I think I can pull it off (but I'm prepared to call in the pros if need be!) Unfortunately there will be no access from the end wall--there's a tiled shower on the other side of that wall.

To the question of replacing the existing trap and adjacent pipe in the event that there's not enough play to attach it to the tub drain, is that how you would go about doing it? (I saw some flexible pipe online, but it looked kind of flimsy to me, especially considering the lack of access to make repairs...)

 

There are some tricks you learn by thinking outside the box...
The waste and overflow should be solvent weld PVC joints, not the brass you have now.
By doing this you can offset the overflow to the side with a 22* or 45* elbow , then drop down to the drain shoe tee. You also swing the tee to line up under the overflow offset. Your horizontal drain shoe pipe will not be parallel to the tub now- but that doesn't matter. What matters is you have effectively moved the drain further away from the trap so you have more room to rebuild the trap to align with the tub.

Something else to consider is using a ram bit to clean out the hub at the wye and rebuilding from there.

I've seen the flex pipe you refer to, but it is used for piping jetted tubs and pumps. It is not approved for drainage piping.

 

Great tips, Eplumber... Thanks! I hadn't thought of either of those possibilities, and that would be great if I could simply offset the overflow as you described.

If for some reason I had to take the second option of cleaning out the hub at the wye, is that something that could be done without removing more of the subfloor, based on the pic I posted? It would be great of that were possible, but I'm guessing that might be tricky...

Let me ask another question, since we're chatting... I'm changing from a jetted tub to a regular soaking tub. What would you do with electric line? It's on its own circuit so I was thinking I would disconnect it at the electrical panel, label it as disconnected up in the bathroom, and then tuck it out of the way somewhere... Is that a reasonable plan?

 

Why not gain access from the room below? Cutting amd replacing drywall is fairly easy.

Sent from my LG-D415 using Tapatalk

 

Why not gain access from the room below? Cutting amd replacing drywall is fairly easy.

Normally, I would agree 100%, but the reason I'm trying to avoid opening the ceiling from below is that the entire first floor of my house has a continuous ceiling, so accessing from below would require a very time-consuming paint job. I'm prepared to do this if I run into problems, but I'm really hoping to avoid it...

 

Second on accessing below. Even if there's light fixture or cabinets there, they are a lot easier to move away and sure thing than your plan. Pipes spin or corroded and trying to precision replumb from above is asking for trouble - even for the pros.

 

Hey guys, I received the new tub, and with it came a couple of curveballs with regard to tying it to the existing plumbing:

-- I learned that the tub has an integral overflow, so I’ll most definitely need to move the P-trap so that it’s under the drain.

-- Looking at the existing plumbing (below), there’s a good likelihood that the “main” drain line will be under the drain.

-- The tub comes with a NIBCO ABS tray plug adapter, hub x NPSF thread. (Pic below.) My plumbing is obviously PVC.

So as I think about how to tackle the new challenges:

-- First, I’m thinking that I’ll try to get a PVC version of the tray plug adapter… It looks like Mueller makes one that might work… http://www.globalindustrial.com/p/p...ng/fittings/PVC/06014-1-1-2-in-pvc-tray-plug-adapter-hub-x-national-pipe-thread

-- As far as the existing drain line being in the way, can I just “offset” a section of it using 4 ells, and then tie into a new P-trap using a tee or wye in the offset section?

-- Question: the instructions that come with the tub say to attach the drain and tray adapter to the tub, prior to installing the tub. Since my plan is to do the install without access from below, I assume that there is no problem gluing the adapter to the plumbing and then screwing in the drain afterwards. (I mean, I know this is how it’s usually done in this situation; I just wanted to make sure that there was nothing unusual in this particular setup that would prevent a tight seal if I screw the drain in at the end… Does this sound OK?)

-- In the (hopefully unlikely) event that I can’t get a PVC version of the tray plug adapter that works, I suppose my options would be to use transitional cement to connect the ABS to PVC, or use a Fernco Qwik Tee to tie an ABS P-trap assembly to the “main” drain line. What do you think would be the best / most-permanent option? (Or would you handle it a different way entirely?)

Thanks!

Allen