Leak under shower pan in basement (newbie)

Hi, everyone. I've been lurking here and finally decided to post because we need some advice. My husband and I are in the midst of demolishing an old tiled shower stall in our basement and enlarging it. When I started demloshing/pulling up the shower pan today, I noticed it's wet under the liner. Very wet, not just damp. It looks like part of the drain (trap?) that is sticking up a little from the floor is leaking...? Not sure what is going on (the 2x4's for the shower curb were rotten but we assumed it was b/c of an improperly built shower pan. Now we think in addition to the shower pan issues, there's something going on with the drain. This is a 100-yr-old home with a 50-yr-old finished basement, and probably a 20-yr-old basement bathroom.

Below are some pics - any advice would be helpful! (I guess at this point, some more chiseling up of the surrounding concrete is needed to see what is going on with all the drain pipes down there that we can't see). Thanks for looking.

Kind of hard to tell, but it doesn't look like you have enough depth to get the trap installed properly unless the shower pan is really thick creating a big step up. Is the liner pvc or lead?

You may need to crack some concrete and check the state of the pipes. If I was going to go to the trouble of installing a new shower, I'd want to probably check and replace the maybe ancient cast iron. It could be in great condition, but it could be totoally rotten.

Can't really see the drain. This should be a clamping drain, and it could have been leaking there from the liner.

Check out www.johnbridge.com for help in tiling a new shower.

On a slab, it's a good idea to use concrete pavers or bricks for the curb rather than 2x4's. If you do decide to use wood, don't use pressure treated unless you use KDAT (kiln dried after treating) stuff which may be hard to find (it is available, though). The wet stuff tends to twist and check when it eventually dries out. Also, put some roofing felt underneath. Still, better to use masonary. Wood's okay on a wooden subfloor, but not when moisture can come up through the slab.

Thanks so much for the reply. Actually, I started posting at Johnny Bridge today, until I found the leak under the pan. Yeah, we have decided to build the curb out of brick and the bench out of concrete block.

We're going to make sure this is done right so we don't have to do it again...

jadnashua said:

Kind of hard to tell, but it doesn't look like you have enough depth to get the trap installed properly unless the shower pan is really thick creating a big step up. Is the liner pvc or lead?

Click to expand...

The liner is PVC. and it wasn't in very good condition. I don't *think* it was leaking from there. How long should a liner last?

The shower pan will be somewhat thick, as the whole bathroom floor is bumped up. You walk in, then step up three inches. So in the pictures, I've removed the previously-built shower pan and gone down to the true basement floor.

jadnashua said:

You may need to crack some concrete and check the state of the pipes. If I was going to go to the trouble of installing a new shower, I'd want to probably check and replace the maybe ancient cast iron. It could be in great condition, but it could be totoally rotten.

Click to expand...

I did some of this last night. Incredibly hard to do by hand! Is there a small automatic tool (electric or pneumatic) that I could use? I'd rather not hire someone if possible, and I'm not ready to deal with a large jackhammer yet. My husband may be up for it, though... The paying work gets in the way of these projects, doesn't it?

What I did discover is the pipe is steel - looks like galvanized. And, there is a rusty area on one side. I can't see the extent of the rust yet since I chiseled for a couple of hours and only uncovered the top 1/4 of the pipe. What I'm afraid is that it runs under the raised (concrete) floor over to the toilet, and that the leaks are over there, too. We recently had a french drain installed on the interior perimeter of our basement to stop seeping and they covered it back up with concrete for us to finish off. (That's how this project started - repairing tile in the bathroom where they jackhammered. Then it turned into re-tiling the whole bathroom, and now we've evolved into replacing the shower stall). I patched the concrete to make it level so I could re-tile it, and it took longer for the cement patch to cure in the area near the base of the toilet. It stayed damp for days after the rest of it had cured. We just ignored that (ha ha ) but now we're afraid it's related to this steel pipe.

This is all coming together now: we've had a slow leak before at the base of the toilet and replaced the wax ring - twice. The leak has disappeared, at least from the floor vantage point. Now I'm wondering what's going on beneath the tile and beneath this raised concrete floor that was added to the true basement floor when this bathroom was added. Oh the joys of owning a 100-yr-old house, especially when previous owners have had their turn at home-improvement projects.

jadnashua said:

Can't really see the drain. This should be a clamping drain, and it could have been leaking there from the liner.

Click to expand...

This drain is a clamping drain, and the concrete around it came off extremely easy. Was a little "gooey"... Could there have been an additive in it?

And thanks so much for the responses... I really didn't think it was the pipe that was the problem but you were right - rusted almost completely through. That's why we're posting here...

There are a bunch of smaller tools that could be used for small concrete destruction. Hilti makes one. A tool rental place will have some choices. Some look like oversized drills that can make swiss cheese out of concrete pretty quickly, then break at the dotted line so to speak. They also can be used with a chisel tip. Wear good eye and ear protection.

Jim,

I bought a Ridgid Hammer Drill today but realized after getting home that it's not what we need for this job. It got hot and was spitting bits of melted filter out on my arms. It's the Ridgid R5011. My husband and I researched some more, and I'm going back to get a rotary hammer, not a hammer drill. That way we can turn off the drill mechanism. We paid $139 for the hammer drill, and the rotary hammer will be $199. Our local tool rental store has a hammer drill for $58/day. Considering future projects we have planned, we're going to go ahead and purchase one, if it will do the job.

Quick question: I was using the chisel bits. Would it be better if I was using plain ol' masonry drill bits with the R5011? It may do the job better that way, given that you can't stop the drilling motion. High RPMs and a chisel bit really *don't* go together...

Mariah

I've only done a little, so am not a great resource, other than what I've read...try the search function. This gets discussed on John Bridge a lot, too.