Tub/Shower Drain Trap question

**bigjon** · 09-28-2012, 04:31 PM

Hey everyone I appreciate all the information shared on this site. With my limited knowledge I've started to redo my guest bathroom. I started a thread over on JB's site because I thought I was just going to demo throw a tub in and start tiling. Didn't work like that. Oh well here I've found some trick and tips and actually got my first leak free piece of copper in.

I started to remove the tub drain and I ended up cutting it out instead. The bathtub I'm installing is 2'' wider so I figured I would have to replace it anyway. I dug down to the trap and decided since I was in there I might as well replace the whole piece from the union on.

My drain had a 2'' Trap then went to 1 1/2''. I went to home depot and wandered around through the plumbing trying to build something of resemblance. I ended up making a piece with 45* streets but all out of 2'' pipe. I could not find the threaded piece on top that the drain screwed into, that my old drain had for the life of me nor do I know the name of what I was looking for.

Question.

Can I use 2'' to the drain and then coupling in (the male threaded piece to match the drain, when I find it)? Does my piece look like it would be ok to replace the old?

The drains I saw today were some rinky dink bs pvc. Is that what I should expect? Is 1 1/2'' the most common since for the tub drain/overflow? I had a brass drain assembly should I go to a plumbing supply store to find that? Rather than the big box stores.

Thanks for the help guys.....

**Terry** · 09-28-2012, 05:29 PM

It's harder to find the brass waste and overflow drains. They had slip joints that could leak later on. Not that you would be apt to notice that in a slab like yours.
1.5" is standard tub drain sizing. The fitting you had for the brass trap would have been a "trap adapter". They carry those in hardware stores. If you use the glue up tub drain, then it's not used.

Having a 2" drain is fine. The plumbers like using a solvent weld p-trap, not one with a swivel. It's just one more location to leak.

**bigjon** · 10-02-2012, 04:51 AM

Thanks for the reply Terry,

I pretty much gathered my pieces both solvent welded trap and a swivel screw on. To try both. The reason I went with the swivel is because that is what was on there and that part of the trap (male elbow) is deep and tucked under part of the slab that still is there. I was hoping to replace from the swivel on, do you see a problem in that other than it just not being a glue in? The same with the tub drain the one I bought is slip jointed because that is what I was replacing.

In your opinion would it be easier to place a tub drain with a slip jointed drain rather than a glue in? Thats my reasoning for not gluing the drain in, that it will be easier for me to position the drain correctly.

hj · 10-02-2012, 06:33 AM

1. The union joints are NOT generic, so even IF the threads would connect, you might not make a leakproof seal, (especially if you are using a PVC trap and the old one is ABS), and since you will NEVER know if it is leaking once the tub is in place, it is not a good idea to try it.
2. Even a new trap can be difficult to get it tight enough to not leak in which case it could also leak after the tub is installed.

**bigjon** · 10-02-2012, 11:33 AM

ahh, not good... My old trap does say PVC DWV on it thought does that make it ABS? Not really sure the difference.

I will take another look and see if I can get to the waste line otherwise I might have to use the old trap all together if I can get it in the correct position.

Thanks.

**jadnashua** · 10-02-2012, 08:59 PM

ABS and PVC are two different kinds of plastic used in drain pipes...generally, you do not want to mix them as the cement is designed to only connect pvc to pvc or abs to abs. ABS is black, PVC is generally a creamish white or ivory color. There are some 'transition' cements, but it's best to avoid them.

**bigjon** · 10-03-2012, 12:54 PM

Wow those union joints were definitely not a match up. A little more complicated than I thought but I've followed ya'lls advice. I completely dug out the trap elbow and cut it off at the line which is 2'' schedule 40.

I feel like I should be dry fitting the tub in place and then gluing everything up is that the normal route? Should I be using the primer then green bottle? Any other helpful advice is greatly appreciated.