Clogged Sink Backing Up Shower and Tub Drains

How Unclogging a Sink Drain Led to a Shower and Tub Drain Clog

By Mark J. Donovan

I noticed recently that my sink drain was draining slowly. So this weekend I decided to disassemble the sink P-trap and remove the clog debris from it. After unscrewing the large P-trap plastic nuts that connected to the bottom of the sink and the drain pipe coming out of the wall I poured the contents of the P-trap into a nearby bucket.

I then proceeded with the disgusting process of scooping out the soap scum and hair from the P-trap and open drain pipes with my finger. I noticed that the drain pipe that fed into the wall had quite a bit of gunk in it that I could loosen up but could not pull out.

After cleaning the P-trap pipe I re-attached it to the straight sink pipe and the drain pipe coming out of the wall. With the P-trap reattached I then turned on the sink faucet and watched the water drain from the sink bowl. All looked great until I went into the adjoining bathroom and smelt an odd smell. I looked down at the shower drain and I noticed water was bubbling up out of it. Immediately I knew that the clump of material I could not remove from the drain pipe in the wall had found a new home.

Clogged Sink Clogged Sink Backing Up Shower Drain

So after shutting off the sink faucet I filled up a bucket of water from another bathroom tub faucet and poured that water into the shower stall. I did this to give me sufficient water in the shower stall floor area to work the plunger properly. To plunge the shower drain I first removed the drain cap. I then placed the plunger over the drain and pumped it about a dozen times. I then stopped and observed that the water still was not draining.

At that point I had my wife turn on the sink faucet in the other bathroom to see if I could push through the clog from the sink area up and out the shower drain area.

Sure enough, as the water from the shower drain pushed up and out all of a sudden a large chunk of gunk (soap buildup and hair) regurgitated out of the shower drain.

After removing the large chunk of gunk I then had my wife turn off the sink faucet and I proceed to use the plunger several more times on the shower drain.

All of a sudden, with a whoosh, the shower drain began sucking down the water in the base of the shower floor.

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With the sink and shower drains unclogged, I finally went back to the other bathroom and tackled the shower/tub drain. I first removed the drain linkage assembly from the overflow pipe on the side of the bathroom tub, and then the shower/tub drain cap itself. I then pushed a rag into the drain and a separate rag into the opening into the overflow pipe. I then filled the bathtub with about 4 inches of water.

Finally, I removed the rag in the tub drain and then pumped the plunger about a dozen times. After confirming the water drained easily from the bathtub I then removed the rag from the overflow drain and reinstalled the drain linkage assembly and shower/tub drain cap. And with that, all my bathroom drains were working like a charm!

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