drain pipe leak- adhesive from within?

[markphin]

I believe I have a leak in my bathroom tub drain as evidenced by a water stain on my cieling below. The drain pipe runs from the tub back against the wall and then must run parallel within the walland ties into the sink drains before going down stairs. It is in the corner of the downstairs cieling (where it meets the wall) where I am seeing the staining. My question is this, I don't believe it is a drain problem as the staining is a good 4 feet from the drain. Is there a product that you can pour down the drain either directly, or mixed with water that would adhere to the inside op the pipe/joints thus sealing up any leak? I am trying to avoid cutting a hole in my cieling.
Thanks for any help!

[HayZee518]

I don't think there is an easy repair for this. It's not like a radiator leak in a car where a pressure leak will stop itself with a leak additive. Water will wick itself along a joist or furring strip and come out in unusual places far away from where it began.

[markphin]

So based on your comment, do you think it may be more likely to be a drain leak(house is 10 years old), and possibly traveling either along the pipe itself or a joist? Whatever it is, it is slight. I guess I could try pulling the drain and replacing the putty seal. It certainly can't hurt right?

[HayZee518]

Ten years old - ABS plastic with furnco joints? or glued joints. really hard to say. you know Murphy's law - if something can go wrong it will! All jokes aside I feel for you. I've been fighting a leaky roof valley for the past four years.

[LazyPup]

Locating the source of a leak when all the evidence you have to work with is a water stain on the ceiling below is without a doubt one of the most difficult tasks in plumbing, however, there are some common problem areas that we can investigate without physically tearing the ceiling out.

Markphin has stated his house is ten years old, therefore it is almost a forgone conclusion that he has either PVC or ABS drain piping. While we think of the process of connecting PVC or ABS as glueing, in fact that is a missnomer. Technically when we connnect plastic pipe the cleaner/primer breaks the glaze on the surface of the pipe and fitting wall. The glue then slightly melts both the pipe and fitting wall and they fuse into one piece in a chemical welding process. Once this is done it is nearly impossible to introduce a leak into that joint. With that in mind, let us now consider other sources of the leak.

First of all, we must understand that when confronted with a small leak the physical amount of water at any given time will be very small, and as Hayzee has previously pointed out, in many cases the water will adhere to the plumbing pipe, framing materials, or even on the upper side of sheetrock by surface tension and may move laterally a great distance before finding a crack, crevic, low spot or seam in the ceiling where it will finally work through and produce the discoloration.

Before resorting to tearing the ceiling out, let us eliminate the obvious:

As Markphin has mentioned, one of the most common causes is the tub drain basket connection. This is especially true if you have a steel, fiberglass or acrylic tub that may flex slightly from the weight of people and water in the tub. The solution, pull the tub basket, clean the mating surfaces thoroughly and replace the plumbers putty or install Silicone sealer.

By code, if your tub has a conventional slip joint type "waste & overflow kit" or a slip joint type P-trap it must have a service access at least 12" x 12" either from below or through an adjacent wall. If there is no service access it must have a glue in type waste & overflow and P-trap. (Keep in mnid that while this is code, it does not necessarily insure that your installation was put in correctly). If you have a service access panel you should begin by opening the cover and visually examine all the piping and fittings.

Here is a tip-take a small mirror such as a ladies makeup mirror. Shine a flashlight beam directly on the mirror and reflect the light into the tight spots. If you will closely look in the mirror while doing so your line of sight is now reflected wherever the light is focused and you will be able to look around corners and tight spots that you cannot otherwise see.

Check the Tub Spout carefully. Often we find corrosion has eroded the underside of the spout and water clings to the underside of the spout, which then runs back to the wall and drips through the wall opening and down on the drain pipe or ceiling below. If this is the case the solution is to replace the tub spout.

Remove the shower mixer handles and trim escutcheons, then look through the hole to examine the handle shaft packing nuts. Look for evidence of water leaks around the packing nuts and shaft. (It is best to turn the water on slightly to get an operational test). If you see any evidence of water leaking around the shaft tighten the packing nuts slightly.

Remove the shower arm and replace the PTFE (Teflon tape) packing on the interior threads. (Do not use the common white teflon tape found in most hardware stores because it is only certified for use on pipes up to 3/8" diameter.

Teflon tape is now being made in different colors to identify the different grades. The proper material for sealing 1/2" to 2.5" pipe threads is the Red "Triple Density" teflon tape, and the triple density tape is only certified it three full wraps are applied in the direction of the thread turns. (You can now find both Red and Yellow teflon tape in almost all of the large home supply centers. The yellow tape is double density and is commonly used on natural gas fittings.)

If you can't find the Red Triple density tape you can use pipe dope.

Next check the caulking around the tub, Water may be getting through the caulking then dripping inside the wall. Also check tile grout or any seams in an acrylic tub surround.



Hopefully by the time you have done all of the above you will have located your leak and won't need to tear the ceiling out.

[SSN596]

Your symptoms could be the result of many problems not related to the drain pipe: the tub shoe gasket, the overflow gasket, a shower stem leak, or a leak the spout attachment or shower arm.

Even if it is a pipe joint, any material you poured into the pipe is sure to be a disaster.

Some detective work with a flashlight behind the trims in the tub/shower, and ultimately opening the drywall downstairs will lead you to the leak.