I have a double kitchen sink with a single s-trap. The problem is that the entire s-trap assembly keeps sliding into the pipe in the floor and sliding off the tail of the pipe coming off the sink. I have tried tightening all the connections. Using different gaskets/washers. Switching from pvc to metal pipes. All to no avail.

We bought the house in '01 and there was a stainless steel sink. At first I thought it was a poltergeist getting his/her laughs. Then I thought that the sink was flexing and pushing down the trap when we washed dishes. Then we put in a new counter top with a new cast iron sink. It is still happening and driving my wife nuts. She keeps an old dishpan underneath to catch the water when it starts leaking.

I am starting to think of blaming the poltergeist again.

I have read every thread that I could find in this forum that refers to s-traps and kitchen sinks and have not found this problem discussed.

How can I keep the s-trap assembly from sliding off the tail of the drain pipe from the sink?

Thank you in advance.

I am currently on active duty with the Army at Ft Dix, NJ. I am going to drive home (NE Pennsylvania) after work Saturday to fix this. I need to be back on Sunday by noon.

Hey Meatballkop:

If this sink is on the first floor then pipes should be accessible from the basement ceiling... yes?

If so, then should just need to purchase a perforated strap hanger at local home supply store and hang waste pipe to kitchen sink from the basement (see pic.).

Other option may be a galvanized F&M ring (x 1.25"?), also available at home supply store...purchase 1.25", 1.5"... see pic.

Also, could replace the nuts and washers... re-tighten...

Get back to me with thoughts... GO ARMY!. Mark

Massplumber2008,

Thank you for the quick reply.

I guess I left out a few things. The house is a “chalet”. That is it has an above ground, block wall “basement”. So I can access the pipes relatively easily. The basement is semi-finished.

The next thing is that an ABS pipe comes up through the floor/bottom of the cabinet and ends. Then the down tail/drop of the s-trap slides into that. Those two pipes are connected with a compression nut and gasket.

OK. That was only two things, but I am sure that there may be more questions.

You really need to secure that pipe coming through the floor. I'll bet it's moving. But a hanger like in mp's left pic probably won't do.

That clamp on the right with a 3/8 piece of all thread and what's called a "ceiling flange" that you can bolt to a ceiling joist will work. I do think there are better clamp options.

MBK:

If changing the compression nut and washer has not worked then:

1) Could replace the desanco fitting (fitting that keeps letting pipe slide down) with a reducing fernco coupling (see pic). Would need to be pipe size x metal size... so for most sinks an 1.5" x 1.25" fernco might do it and then can just cut off old desanco and install fernco and CLAMP the parts together at height desired... guarantee will not slip past the tightened fernco if ABS pipe below is supported well.

You said you had a metal s-trap into sturdy ABS pipe below... why not change over to ABS pipe throughout with a new PTRAP and AAV (air admittance valve)... see pic.(pvc here, but you get the point.. and I would stay solid ABS right over to tailpiece from each sink strainer) I know you have a double sink... so would just add a sanitary tee ABOVE inlet to trap to pick up other sink... this is a bit more work, but will drain better then with strap and will definetely not fall off IF you install a hanger such as the f&m split ring I showed you in my last post at the outlet of the p trap.

Just a couple more ideas for you... Good luck... Mark