I am replacing a bathroom vanity and while I'm doing that, I'm also replacing the p-trap for the sink (mostly because I want one with a drain, but also because I have to raise the height a couple inches) . Right now, there is a 1 1/4" female drain connector sticking out of the wall (which takes 1 1/4" I.D. pipe). The old P-trap was made of metal:

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My intention was to use a standard 1 1/4" ABS P-trap, however, ABS is 1 1/4" O.D., and the drain connector takes 1 1/4" I.D. The edge of the connector is about 1/8" recessed from the drywall, which will make cutting that piece off and attaching a coupling fairly difficult, though may be possible. I don't want to actually open up the wall (as you can see, I'm already in the process of patching the messy hole someone made for this pipe).

Anyone have any better suggestions?

  • take the trap with you to the hardware store, I'm sure somebody there can help you find the proper fitting. This seems like it would be a common problem, so I'm sure there is a solution available.
    – Tester101
    Commented Aug 2, 2011 at 16:31

3 Answers 3


A 1 1/4" female FIP adapter worked perfectly. As soon as I saw it, I was embarassed for not having thought of it earlier.

enter image description here

I used some teflon tape, screwed the FIP adapter onto the adapter coming out of the wall, then just glued my 1 1/4" pipe directly into it. No reduction in pipe sizes, and 100% ABS parts.

enter image description here

  • 4
    Nice work, we don't get enough 'after' pictures around here.
    – pboin
    Commented Aug 18, 2011 at 10:48

I have made the mistake twice of demoing an old bathroom sink and throwing out the p-trap before the new sink and plumbing went in. Both times I regretted it because when I went to put in the new p-trap, I found some sort of strange/different plumbing setup which required several trips to the hardware store (and me repeating to myself "why did I throw out the old p-trap!?!?").

My recommendation is to use the old p-trap. Take some rags and steel wool and clean it inside and out and you should be able to get it looking like new. (And while you are at it use some rags to clean out the connector in the wall too since that looks pretty dirty too.) And then you can get a drain extension tube to raise the height up to your new sink fairly easily.

The only issue is that the distance from the wall of the old p-trap may not match your new sink. In that case try using part of the old p-trap to attach to the drain in the wall (since you do not have any extra pipe to work with) and then use a coupling to attach your new p-trap to this steel pipe. (Although not sure how easy it would be for you to find a coupling for you to attach to that steel pipe.)

  • My biggest issue is the lack of a drain in the P-trap. This means if something gets dropped down the drain, there's no retrieving it without taking apart plumbing.
    – gregmac
    Commented Aug 1, 2011 at 14:34
  • 1
    A drain in the p-trap is definitely a nice-to-have, but I have always found it easy to take apart a p-trap for retrieving items (especially the ones made of ABS plastic). Commented Aug 1, 2011 at 14:41

Best way I've thought of so far is to use a drain tube extension coming out of the connector in the wall, then go into another female trap connector, then P-trap, and then finally female drain connector for the actual sink drain. Biggest downside is the pipe will get narrower between the wall and the p-trap, since it's 1 1/4" OD. On the upside, it'll be easy to take the p-trap off and clean it all out.

  • hmmm... would that be up to code? I am not sure a tube extension on the smelly side of the trap is allowed. That seal may not be good enough to prevent all fumes from entering the room. Commented Aug 3, 2011 at 1:36
  • Good point - unfortunately though, that's what was already in the wall and probably has been there for 30+ years. The only way to change that though is to take down all the drywall, cut the existing pipe back and re-run, and then patch it all up. I'm really trying to avoid that for something so simple.
    – gregmac
    Commented Aug 3, 2011 at 4:08

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