I have shower stall, which is 25 yo with a lead pan installed (saw it done). The pan appears to have developed a leak near the drain.

I've dug out the grout in the vicinity of the drain, and if I pour a couple of oz of water there, it immediately leaks to the ceiling below (cut the drywall, and installed a plastic catch basin to observe).

Previously, the grout was resealed, but the weepage continues. Removal of the grout, seems to demonstrate that the lead pan has failed. One plumber friend suggested a waterproof grout, but I can't seem to find any, nor does he have experience with this.

I'm open to suggestions, but for several reasons, would like to avoid complete teardown of the shower right now.

Anyone with experience with this?

The lead pan can be re-wiped with lead solder and flux, but I wouldn't trust this job to just anyone, wiped joints are a practice that went out decades ago, and few newcomers to the trade have ever done it, let alone watched it being done.

I'd call around to a few different plumbing shops to see if they have anyone in house who has done this kind of thing before.

Rewiping could be conceptually done, but practically I don't see how. The lead pan has a mortar base below it, and some kind of cementous material, which I recall was thinset, on top of it. Then there are the tiles. So getting to it is a problem.

I suppose pouring lead into the grout lines of the tile might get lead there, but I doubt that it would bond well.

I suppose injecting an elastic epoxy would be doable, but again, I have not seen any reference to this in any literature.

Again, I welcome ideas... because I'm at a loss. Thanks

As a old timey plumber that had to wipe a lead joint to pass the license exam I have a suggestion. The last lead shower pan I installed was back in the middle 70's. That's about 30 years ago. Who knows how many other potential leaks there are down there? You can load the area up with epoxy and pray like heck the you've caught the leak and that it holds. But if it doesn't my suggestion would be to rip out the lead pan and replace with a plastic shower pan. I realize this is a unpopular answer but this just might just be what you end up doing. Good luck, Tom PS. I still have my lead working tools in case anybody want's to give floating a patch over the leak a shot.

I believe the reason a lead pan was used is that the shower dimension is non-standard. Is there broader selection in plastic?

The second part of the story is that I'd rip out the shower, and reinstall a new on... but I need to do that in another year. I have another bathroom that needs structural floor work. As a result, I would like to get this shower serviceable, and can then redo after I get the other bath complete. Things are complicated.

So let me explore another option... can I lay a liner of some sort down, put tile over it, and have it drain into the center of the existing drain?

Hey Bird,
"I believe the reason a lead pan was used is that the shower dimension is non-standard. Is there broader selection in plastic?"

Yes there's a wide selection in plastic. We use Blue Composeal 40 mil to pan out our showers and have never had to replace a pan yet. To check it out
Click on; http://sweets.construction.com/mfg/425/P36324.htm

"So let me explore another option...can I lay a liner of some sort down, put tile over it, and have it drain into the center of the existing drain?"

Good idea! Too bad it won't work. You are proposing to pan out the shower over the existing tile, (and leak) and then retile. In order to seal the drain assembly a flange type shower drain, (see image) is installed. This not only clamps off the shower pan, tile and mortar, but also provides weep holes for any excess water that may work its way down the mortar to drain back into the system. You can't install this type drain over another and if you pan without it you would still have the same problem.
If you don't wish to redo the shower at this time I would load the area up with epoxy, (do not epoxy over the weep holes) and test by blocking off the drain and weep holes and filling the base with a inch or so of water. Let it set awhile and check for leaks. If after a few hours there aren't any patch the floor.
Good luck. Tom

The drain you show a picture of is what I assume I already have (in brass and who knows what else). I'm also assuming that my breech of the lead pan is very close to that drain.

Oh, I can run a garden hose down the drain all day, and there is no leakage. But pour 3 oz of water into the grout removed from the tiles around the drsin, and the water runs immediately out, in the vicinity of the drain below the floor.

So to just play with the idea a little more... if I install a new pan, above the existing tile floor, and drain to a smaller diameter drain, and place that INTO the existing drain, then the very small leakage from around the new membrane would propagate to the existing pan, and leak to the ceiling below. Ideally, it would be a very small amount.

Oh, how do you propose I install a sealant and avoid the weepholes? Remove the tile in the vicinity of the drain, and dig for the weepholes?

Thanks.

"So to just play with the idea a little more...if I install a new pan, above the existing tile floor, and drain to a smaller diameter drain, and place that INTO the existing drain."
Boy! You don't give up easy do you? You would have to locate a flange type shower drain to small enough to set into the old drain with a water tight connection and I don't know of any such creature. Also It would raise up the shower floor to almost the height of the threshold.

"then the very small leakage from around the new membrane would propagate to the existing pan, and leak to the ceiling below. Ideally, it would be a very small amount."
You're assuming it would be a very small leakage while I'm assuming the leakage would be in direct proportion to the amount of time you spent in the shower.
"Ideally, it would be a very small amount."
Theo! ANY leak is unacceptable.

"how do you propose I install a sealant and avoid the weepholes? Remove the tile in the vicinity of the drain, and dig for the weepholes?"

The weep holes are simply grooves cut into the top part of the drain clamp. Just keep the epoxy away from the shower drain clamp.
You can mortar around and over the weep holes but you can't epoxy over them and seal them off. Cheers, Tom

OK, I see the grooves in the plastic drain I picked up to help me understand the problem. And if I understand you correctly, the mortar is OK to get up to the weep holes, because it will pass some water, whereas the epoxy will not.

Sounds like I have to chisel off some tiles. I suppose I'm using a cold chisel, and shouldn't grab my air chisel from the garage, eh?

BTW, thanks for the material reference to the 40 mil plastic for the new pan.

It occurs to me that if I get a realtively free flowing epoxy it might work better than a more viscous epoxy.

Thanks.

One more thing... so I have a chance of getting the drain to turn to spin out, or should I just forget it? If I could break the mortar matrix with it, then I could attach the area from below the drain, and then screw the drain back in. Mine is brass, so probably not. I've also thought about cutting it out, and working on the area, and then cleaning things out enough to screw in a plastic one. I realize that I might have some work to get it flush with the time surface. This would have the advantage of potentially allowing me to break up less tile. (I'm thinking sawzall on the pipe section, and a dremel type saw on the flare of the drain near the top.)