A modest sized object had fallen into my bathroom sink causing (I assume) the sink to drain slowly. That is, at first (after dropping the item) the sink seemed to drain fine but eventually it slowed to a bare minimum.

The sink is a pedestal sink and the drain pipes are pvc with threaded and compression joints, so I took out all the pipes from basin to floor, clean everything (obstruction and all) and put it back together. Everything was hand-tightened only: the only tool used was a toothbrush to scrub the parts clean.

Now the water drains better but only slightly. If there is still an obstruction, it would have to be in the floor, but we had no apparent problem before the one item I was able to extract. On the other hand, now, as the water slowly drains, I can hear a trickle in the drain pipes. As far as I can recall, this was not the case before I took it all apart. So I'm guessing that there is air bubble somewhere. Does that sound reasonable? And if so, what can I do to deal with it.

Note that this is not a new works project; I simply disassembled, clean and reassembled everything. I didn't add parts or have any parts left over. At worst, I might have changed the order of parts or changed the spans between adjustable, compression joints. But all the fittings and seals were put in place.

  • 1
    No, it doesn't sound reasonable. Drain pipes are full of air except when something's flowing through them. You have another obstruction somewhere.
    – isherwood
    Mar 29, 2016 at 17:19
  • Are you sure only one modest sized object fell into your bathroom sink? The first object might have gotten past the floor. As Ed Beal says, a hand auger should find it. Apr 9, 2016 at 15:24

3 Answers 3


There is probably soap and hair plugging the drain lower down. a small hand auger might be the best bet to clean it out. Chemical drain cleaners partially open the drain then they plug up again much quicker and you end up spending more on chemicals than the cost of the auger.

  • so are you saying the hollow trickling sound, as water drains, is irrelevant?
    – codechimp
    Mar 29, 2016 at 18:13
  • I believe the hollow trickling sound may in fact be the water dribbling from the plugged location.
    – Ed Beal
    Mar 29, 2016 at 18:48
  • I find the opposite with chemical cleaners for hair/soap. A plunger on the shower drain works for a little while but the returns diminish and eventually a dose of caustic soda is needed which sorts things out for months.
    – Chris H
    Mar 29, 2016 at 19:43
  • 1
    I said nothing about a plunger Chris H. I said an auger (this scrapes the pipe and hooks into the hair and removes it) Once your caustic soda goes down the drain it is killing your septic system or has to be treated if on city sewer. If the plug partly breaks up there is nothing to hold the chemicals in place so it plugs up faster.
    – Ed Beal
    Mar 29, 2016 at 19:53
  • The item that dropped in & then was additionally pushed through gunk & into the trap by water probably just dislodged some gunk to create a clog further down the pipe. The Auger or something similar should get it clear.
    – Iggy
    Mar 30, 2016 at 3:18

Even though based on the sound of the trickling (based on the clearness and loudness near the double-trap) I suspected the"obstruction" was NOT in the floor but rather in the PVC drain pipes, based on the suggestions given here, I had resigned myself to the idea that I had more work to do on this project and waited for a good time to tackle it. The we still used the sink since it still drained, albeit slowly.

However, before I could get to it, the "obstruction" cleared itself and now the sink drains very well. Now, a basin full of water drains in <10sec with good vortex action. I can't believe that hair/soap in the floor, could clear itself so well without help, and I know with 100% certainty that the above-floor pipes were free and clear of hair/buildup. So now I'm fairly convinced that the obstruction was NOT hair but in fact was some air bubble trapped near the double-trap.

  • 1
    If you can trap an air bubble in a drain pipe you have big problems. By their very design air moves freely in one direction while water moves in the other. I love it when a problem heals itself though. 😆
    – ArchonOSX
    Apr 9, 2016 at 18:28

Probably blocked vent. Sometimes leaves. Even though there is such a thing as ventless drains that work very well, they r rare. Yours more than likely has vents. I remember one time nobody could figure out why this poor guys basement bath sink wouldnt drain. It took me about 20 minutes to clear the plugged vent. Then magjic. Drained like u wouldn't believe. I might of saved him from his second heart attack. First one was after 2008 crash.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.