plumbing leak in shower and bath

[rich home]

I found that my shower and bath in the master bathroom are leaking down the outside of the drain pipe. The shower is a tile and glass shower and the bath is also covered in tile only on the outside of the tub so tearing either out will be a hugh pain. It isn't leaking much but the water is following the 3in drain pipe into the basement where we first noticed the leak. I have removed the sheetrock from the basement ceiling in the area of the leak. There is also a 2nd bath on the 2nd floor that is not leaking at all. I really don't want to tear into the walls since I haven't noticed any water stains on the 1st floor where the pipes run through only in the basement. As you know tearing out the tile would be a hugh pain so I want to avoid that if at all possible.

[LazyPup]

Locating an unknown leak inside of a wall can prove to be a very challenging undertaking, but there are a number of things we can do to find it before we resort to tearing walls out.

We must keep in mind that even though the water is visible on the pipe below, that does not guarantee that the leak is originating from a drain pipe. The water could be leaking from a point above a horizontal drain pipe, then cling to the pipes by surface tension and run a considerable distance until it finds a low spot and drips off or reaches a vertical pipe and runs down the outside wall of that pipe.I once spent three days looking for a plumbing leak only to finally find out it was a roof leak at the base of a Citizens Band Radio Antenna mast on the roof, which was allowing rain water to drip down into the attic, across a truss and dripping down the plumbing vent chase leaving the impression that there was a leak on the vent stack.

Locating leaks is one of the tasks of a plumber which really cannot be taught in the classroom because each situation is a bit different. Fortunately we do learn from experience, so allow me to share some of that experience with you and perhaps we can find your leak without tearing the walls out.

The first step in locating a leak is to have a thorough understanding of how all the piping is connected inside the walls. From this we can surmise some of the potential sources of the leak.



You stated that your tub and shower are tiled and there is no mention of a service access panel therefore the waste and overflow kit should be a glue in type as seen in the above illustration.

In a glue in style kit the TEE, Shoe, and Overflow body are cast PVC parts which are then interconnected by 1-1/2" PVC pipe cut to fit and it is all glued together. When completed there are no mechanical joints which could create a leak.

If you will examine the TUB SHOE you will see that it has a rubber gasket that fits on the top of the shoe and is pulled up tight against the underside of the tub when the drain basket is screwed in. Either plumbers putty or silicone is applied under the flange of the tub basket to seal it to the tub. This is perhaps the most common failure point, especially in fiberglass tubs which tend to flex slightly from the weight of people standing in the tub while showering. I would recommend using a Basket Wrench to first remove the tub basket. With the basket out you should be able to press downward slightly on the tub shoe and insert the tip of a silicone sealer tube spout between the top of the rubber gasket and bottom of the tub and apply a good film of silicone on the gasket. You can then apply silicone or plumbers putty on the underside of the tub shoe flange and screw the drain basket back in tightly. (If you use silicone you must wait 24hrs for the silicone to set before running water, if you use plumbers putty you can run water immediately after tightening the drain basket in place.)

It is possible for the gasket behind the overflow to leak if you fill the tub up to the overflow, but it is very highly unlikely that you will have a leak there if just using the shower.

You stated that you have removed some sheetrock from below, so this would be a good time to examine the Waste & Overflow, P-trap and drain line connections to be sure they are not leaking. They should all be glue joints so the likelihood of a leak is very small.



Carefully feel the underside of the tub spout, especially near the tip where the water comes out. Quite often the chrome finish will corrode leaving a very rough surface on the underside and eroding the rear part of the nozzle away. Once this happens water will cling to the underside of the spout by surface tension, run down the underside and eventually leak inside the wall. The solution is to first replace the spout, then apply a bead of silicone caulking to seal the spout at the wall however, if your spout shower diverter is built into the spout, do not seal the spout to the wall. Diverter spouts have a weep hole on the underside so that if the diverter valve leaks internally the water inside the spout body will drip our the weep hole and down on the tub apron rather than going in the wall.

Remove the faucett handle and Trim Escutcheons, then using a flashlight, look in the hole to see if you can see any evidence of leaking inside. Pay particular attention to the packing nuts at the base of the faucett handle stem shaft enters the stem unit. Also check where the faucett stem assembly connects to the mixer body. If you see evidence of leaks there you can use a plumbers socket to reach in the hole and tighten the stem assembly or the packing nut. (You can buy a complete set of plumbers sockets in any hardware store for about $10)

Next check the shower arm connection. First slide the shower arm trim escutcheon out on the ahower arm pipe away from the wall, then examine the threaded connection where the shower arm connects to the shower riser. If you see any sign of leak here unscrew the shower arm pipe and clean the pipe threads with a small wire brush. (a copper fitting ID brush such as used when soldering is excellant. They can be purchased at any hardware for about $1).

Now apply 3 full wraps of RED TRIPLE DENSITY teflon tape or pipe dope to the threads and re-install the shower arm pipe.

Check all caulking joints in the tub/shower enclosure. If they appear loose the best solution is to cut out the existing caulking and install new caulking.

At this point you will most likely have found and resolved the problem. If not, and if it is necessary to open the walls up, it is best to try to come in from the backside of the wall from another room. In this manner you will only have a simple sheetrock repair instead of replacing the tile.

[rich home]

Lazypup

Thanks for the info, it helped me do some troubleshooting, and other tests but it looks more and more like I have a leak in the 3in pipe somewhere or at least to my untrained eye. Here is what I found since your response.

First I need to clarify a few things. First of all the bathroom is on the 2nd floor and we are not noticing any water leaks in the ceiling on the first floor, only in the basement, coming from the edge of the cutout that touches up to the 3 inch drain for that bathroom. THat pipe runs through a wall in the first floor between the kitchen and Dining room. The shower and bath are seperate, and they only leak when the water is draining. I plugged the drains and filled the shower up to a comfortable level to test the pan and it did not leak. I also did the same thing with the bath, although I did not run water into the overflow drain. With the drain plug in place it did not leak until I let the water out of the tub. Once again not a lot of water but enough to notice running down outside of the 3 inch drain line.

I went ahead and changed the tub drain (basket) assembly thinking it would be good to concentrate on one seal just in case it was an easy fix. I repacked the fitting with the plumbers putty and just for good measure I wrapped the treads with plumbers tape. I thought I had the leak sealed when my daughter flushed the toilet on me...I can't complain my helper is 2 years old. When she did that i noticed the leak started again. Great new leak or so I thought. Then it made we think a bit more. We have two sinks in that bathroom why not check them while I'm at it. Guess what they showed the leak also. (again only when the water is let out of the drain).

Is there anything else I can do besides start looking behind the walls? I have to admit this is giving me a few headaches as I'm not looking forward to tearing into the walls. I think I can access the initial turn behind my daughters wall, but I'm not certain. Should I use a food coloring dye to give me a better idea where the leak is starting? Any advise is better than some of my crazy ideas. Thanks again

Rich

[LazyPup]

There is still a number of things you can do before tearing the walls down.

In order to determine the next course of action I would need to know what kind of pipe you have? I.E. Cast Iron, Copper, PVC, etc.

In the mean time, here is a trick that will help you look into the tight places.

Get a flashlight and a small hand mirror.(A ladies hand makeup mirror works great, I actually have one about 2.5" x 4" that I keep in my toolbox for such occassions).

You can reach the mirror up into the open floor cavity and use it to look back behind or above the pipes.

If you will shine the beam of a small flashlight directly into the mirror, the mirror will reflect the light to the point you are looking at and you will be able to see a nice brightly lite image in the mirror.

[rich home]

PVC

I would have to cut a hole into the wood in the flooring on the first floor IT's very tight. I'm very familiar with the technique and will try it. I also can acess the walls via an opening in the ceiling on the 1st floor...(just replaced a florecent light with a standard light. That might let me see the first bend before it goes behind the wall between the kitchen and the dining room, or at least let me me see where I can get a good look.

Rich

[LazyPup]

Fortunately you have PVC pipe which means there should only be joints in the pipe at points of intersection with other pipes.

With PVC pipe we can also rule out acidic corrosion through the pipe walls such as we might find in copper, brass or lead pipes.

We can now use a bit of basic plumbing theory to try to pinpoint the source of the problem a bit more.

The three cardinal rules of plumbing are, Hots on the left, colds on the right and the stinky stuff flows downhill. (rule number 4-don't bite your fingernails).

Now understanding that the drain pipes are all pitched at 1/4" per foot dropping in the downstream direction we can use a bit of deductive reasoning here.

From your investigation you determined that the leak appears when the watercloset if flushed, the tub is drained or the lavatory is drained. Obviously the leak must be at some point downstream of those fixture drains.

The water closet (Toilet) requires a 3" diameter drain line and the Water closet is required to be set on the end of a waste arm, it may not be downstream of another fixture on the same line.

You know the position of the water closet and the position of the vertical vent stack, so you begin by imagining a direct line from the base of the water closet flange to the stack.

Now imagine a line from the tub drain that intersects with that 3" line. That is the approximate location of the tub waste arm.

Imagine another line from the base of the lavatory drain to the 3" pipe.

By this time you should have a rough estimate of where the tie ins might be so you can begin your search between that point and the stack.

Now let us rule out the obvious. You stated that you had just installed a new light fixture. Is it remotely possible that in the process of installing that fixture that you may have run a saw blade or a screw in the vicinity of those pipes? Have you done any home repairs in the vicinity of the pipes that could have resulted in hitting a pipe with a saw or a screw? (I once found a pipe with 8 screws in it where the homeowner had used 3" deck screws to put up a small sheetrock patch).

If you can access the Sanitary Tee where the 3" horizontal drain line connects to the vertical stack check the joint carefully. That joint or the next joint upstream from that location toward the watercloset is mostly likely your point of leak.

[rich home]

LazyPup

Thanks for all the help. We found the leak and of course it was self induced do to our remodeling work. We put a finishing nail into to the pipe and it was the source of our problem. You saved us a ton on money and work and we are indebted to you.

The world is a much nicer place with wonderful people like you around. Please take care and have a very happy holiday season.

[LazyPup]

Thank you so much for coming back and telling us what the final outcome of your problem is.

Just out of curiosity how far was my estimate from the point where you actually found the leak?

Hopefully the problem is in an accessible spot that won't require too much demolition to make the repair.

Here is a tip. if the hole is in a PVC drain pipe, and if it is only a small nail hole you could fill the hole with clear silicone, apply a patch of rubber over the hole sealed with silicone, and secure that in place with a metal radiator clamp. This would preclude the necessity to cut a pipe out and replace it.

[rich home]

It was in the same line/area as you described. It was a bit further down line from the merge of the WC and the shower and other drains. We had put in a chair rail and luckily found the pipe with a finishing nail about 30 inches up from the floor. When I was pulling the chair rail off I noticed the rust building on the nail and the slightly damaged sheet rock. Honestly when you stop to think about it, and take a few minutes to look around the area it was very easy to find. I ended up only having to remove a 2X4 inch section of sheet rock to find the whole and patch it as the rest of the area. I injected 5 minute epoxy into the hole let it set then covered it with locktite houshold adhesive (seals to a waterproof/watertight finish) and then the rubber and clamp as you suggested. Letting it set up over night and then will check in the morning and finish the sheet rock patching. The boss has already said I will be using glue and not nails in that area when I put it all back together. Thanks again, I will send others to this sight when the next home improvement question comes up. That way they can get the answers without all the BS from the other 2 sites I used to get ideas on the repair.