How would you convert this old copper shower drain to PVC?

[Tdkdpt]

Remodeling my shower and trying to convert this old drain to PVC. Does this plan work ? How would you do it?

 

[Jadnashua]

If you unsoldered the elbow to the existing trap, you could likely have more than enough length to just convert to pvc right there. You'd need the right shielded coupler to account for the diameter difference between the copper and PVC, but they're available.

SOme of this would depend on exactly where the new drain must be centered. Cutting back more will give you a bit more flexibility.

 

[Sponsor]

 

[Tdkdpt]

If you unsoldered the elbow to the existing trap, you could likely have more than enough length to just convert to PVC right there. You'd need the right shielded coupler to account for the diameter difference between the copper and PVC, but they're available.

Some of this would depend on exactly where the new drain must be centered. Cutting back more will give you a bit more flexibility.

Yeah I considered that as well, as shown in this picture. It may get a little tight as the new 2" PVC is more bulky but I need center to be at that red dot. Would that shielded coupling work if I cut into that 45 deg joint before it heads into the joist? Or do they just fit over the old copper straight piece?

 

[Terry]

Kind of looks like it needs to be cut to the right of the joist there.
Maybe replace the 90 there.

 

[Jadnashua]

THe shielded couplings won't fit over the fitting...they're designed to only fit on the stock pipe. They come sized to fit over copper, CI, or PVC/ABS, so you need to get the right one so it will properly seal to both types of pipe. Depending on the size of the hole through the joist, you MIGHT be able to keep the 90 there, and convert to PVC with a shielded coupling, but it probably wouldn't work as you may not be able to tighten one end if it didn't clear the joist.

Keep in mind that you can't dry fit PVC pipe...the fittings are tapered, so you can't get the pipe seated properly until the cement melts the plastic, so careful measuring is required if the drain must be in a very specific place.

 

[Tuttles Revenge]

If it were me, I would cut out that copper 90 and drill a new hole in the joist. Use the extension from the new 45 and the swing of the trap to get your center exactly where you need it to be.