Shower - leaking water through wall tile?

**PIZ** · 06-07-2006, 08:36 AM

I was down in my basement the other day. I noticed water leaking onto the basement floor, coming from the area where our shower is located. So, I went upstairs to see if I could find a place where the caulking was ruined, but couldn't find any problems. I did notice some wall tiles (about 5) that seemed loose, meaning if I pushed on them they had some "give." Would enough water be able to get through those loose tiles? Enough that it would leave a small puddle on the floor?

This only happens when we take a shower, but not everytime. It does not happen when the tub only is used.

I really don't know where the water is coming from. What is the most common cause? Caulking failure, wall tile leaking, main tub drain leaking, overflow for the tub leaking, pipe going to the shower head leaking?

Also, if I replace the loose shower wall tiles, what kind of adhesive should I use? Is there special adhesive for shower tiles, maybe waterproof adhesive?

Thanks for your help.

**chassis** · 06-07-2006, 10:41 AM

If you have water getting out of the shower, it is coming from these possible sources:

- failed shower pan
- improper tile substrate and backing
- plumbing (pipe or fixture) leak

You need to rule out each one. Loose tiles tell me that there is a substrate issue. Did you build the shower, or have it built by someone? If yes, what tile adhesive was used? If it was pre-mixed (also known as "mastic"), then that is the problem. Also, if the backer behind the tile was not cementitous (cement board, or equivalent), then even if the proper adhesive (thinset) was used, the drywall can get wet and mushy.

Even if the grout and caulk are perfect, if mastic or drywall was used in the shower you will eventually get leaking.

A failed shower pan takes a little more sleuthing. The wall tiles that are loose - how high up are they? If they are near the bottom, it could be you have the weep holes plugged in the shower drain, or there is no pre-slope under the tile. This would cause water to acumulate, and if the proper adhesive was not used (see above), you will have problems.

From your description I don't think you have a leaking pipe or shower fixture.

If you can post some photos of the loose tiles, and of your shower in general, people may get a better idea on what to suggest as a solution.

**PIZ** · 06-07-2006, 11:19 AM

I bought the home 2 years ago, and the home is about 50 years old, and we didn't remodel the bathroom. To describe the tile: The same tile (4" x 4") are on all the bathroom walls and inside the shower. To describe what the loose tiles look like: They are still intact, but you can see where the grout is loose around one side of the tile and if you push on the tile it moves in a little when you push it. I have no idea what kind of adhesive was used or what kind of backing. It must have been decent materials, because as far as I know it lasted 50 years. The loose tiles are all near the bottom.

I'm embarrassed to say, but I have no idea what you mean by "shower pan" and "weep holes."

I think I'll start out by replacing the loose tiles, but what kind of adhesive should I use. Also, if the loose tiles was caused by plugged weep holes, how do I unplug them?

Note: I just Googled weep holes and shower pan. I think I should have described by shower/tub. Our shower/tub has a large tub, big enough to lay in, and the shower on the front wall.

Could these loose tiles really be the source of leaving a puddle on my basement floor?

**chassis** · 06-07-2006, 01:16 PM

PIZ,

OK so you have a tub, this rules out any issues with the pan.

But since the tiles are loose, it's still possible the backing behind the tiles is not waterproof. If you want a long term fix, I think the best bet is to redo the shower surround with a new vapor barrier (felt paper or plastic sheeting) and cement backer board. A short term fix may involve waterproof adhesive from Home Depot or Lowe's, but I don't recommend this.

If the tub is above the part of the basement where the leak is, the loose tiles would be my leading candidate for the leak. Photos would really help in further advice/diagnosis.

**plumber1** · 06-07-2006, 02:22 PM

Water is probably leaking from more than one place. It would be really nice if you had an access door for the tub. You wouldn't have to guess, you could literally see lots things. Other wise your just groping around in the dark.....

**jadnashua** · 06-07-2006, 03:55 PM

If the tile are loose, then, as mentioned, the substrate is shot. It was probably installed right over drywall or maybe greenboard (almost the same thing); neither of which is acceptable by code for use in a shower (as of this year in the national codes). If the tile are loose, tearing them off will probably reveal some mold and rot. Could be wrong, but my gut says not likely. If you are really lucky (well not really or you wouldn't have this situation), you can peel off the loose tiles, clean some mastic off of them, clean things up and use some thinset to replace them - as said, I think the wall is shot - probably drywall, and wet.

If the people that owned the house before you didn't use that shower much, or just used it as a tub, they may not have noticed the problem.
A good way to build a wall in a surround is with a vapor barrier, cement board (cbu), then tile.

Get some expert tile masters' opinions over on www.johnbridge.com.

**Gouranga** · 06-08-2006, 04:22 AM

Since it was brought up here guys. What I was told (and hopefully you can verify) that the grout in a shower is not waterproof. Neither is backerboard. This is why you need that vaporbarrier. I had a friend who was told my Home Depot that the hardibacker (the one with the display where it underwater) was waterproof. After he built the whole thing, he found out otherwise. That Hardibacker would only not warp, in water but was in no was waterproof. He called the manufacturer who confirmed yet Depot will still tell you it is.
From what he was told by a pretty good plumber, If your shower begins leaking as yours sounds like it is, the only way to fix (permenantly) is to tear out the surround and redo in the correct way. If your tile is moving though, it sounds like at the least your backer (whether sheetrock, greenboard, or actual backer board) is shot at leats in that area. I guess what you are looking for is to at least short term, plug the hole in the dam so you can properly prep for a full redo.
So guys, for his sake, and all of our general info, what is the best way to get a temp fix in place for this type of thing?

**PIZ** · 06-08-2006, 04:45 AM

WOW!!! I really didn't think the problem I had was so potentially bad. I thought I'd have an easy permanent fix. I'm almost afraid to pull those loose tiles off, because of what may be revealed. As you might have guessed, I'm no expert, actually I'm just a novice who likes to try things myself before calling someone to do it for me. If I would just replace the loose tiles with new adhesive and new grout, how long could I expect it to hold up, given the backing is not rotted away?

I guess the easiest solution would be to have everyone in the home start taking baths only.

**Gouranga** · 06-08-2006, 05:16 AM

Do you have an extra bathroom in the house? Maybe I am sick, but I get a lot of enjoyment out of an "opportunity" in my house like that. I mean if you have the financial means, and do some research and planning you could do more than just a redo. Could build the B-Room of your dreams! And doing it yourself, you get a good sense of pride in it. The biggest thing is knowing your limitations and hiring the pros when a particular item exceeds them.
I will usually do the same thing though, most things I will do myself, if I have any doubt on something I will at a minimum pay a professional to at least inspect (and sometimes redo) anything I have done. I have a local guy I usually call ahead of time when I am doing something. I let him know way out so he can just stop by at his leisure when I think inspection time is coming. He redoes less than he used to.
We had a very slow leak in a feed line ot our fridge icemaker a while back. Something simple small, should never be a real bad thing right? Except, because it was soo dang slow, it dripped through the plastic recess it was in, and had eated a channel through the sheetrock down the the floor. I ended up having to tear out the sheetrock behind the fridge and in my home office (other side of the wall) getting some nice chemicals to kill off all the mildew in the wall, and rebuilding it all. One of those tip of the iceberg things that seem to occur quite frequently at this house.

**jadnashua** · 06-08-2006, 05:45 AM

If the wallboard is shot, nothing other than a replacement will fix this problem unfortuneately. And, if it is letting water into the walls, you will eventually end up with mold and wood rot. Better to bite the bullet now than replace structure later along with the (likely) increase in mold. Note also that carpenter ants love wet wood, and can make swiss cheese out of a structure while dining. Hope it is some simple fix, but I doubt it. Better to find out now. Check out www.johnbridge.com. Even if you don't want to do it yourself, you can find out how it should be done to last, and make sure it is done that way. In the interim, take a towel and wipe off everything in the shower after each one. You could put up some plastic on th ewall with some tape (ugly, but keep the water offf the wall for now).

**plumber1** · 06-08-2006, 05:55 AM

It's a given, you need to repair the things you see, but you can't see the the business side of the tub nor can you see where the leak is. And you could do that with an access.

**PIZ** · 06-08-2006, 06:17 AM

I'm going to post over on John Bridge also. Thanks for your help guys.

**plumber1** · 06-08-2006, 08:44 AM

I think that at Terry's site you will get better answers about leaks like yours than at John Bridge.

**jadnashua** · 06-08-2006, 11:45 AM

The moderators on that site focus almost exclusively on tiling, with many of them heavy on showers. When you do it every day (and they often call a plumber in to do the drains or supplies which we don't think is th eissue here), for the structure of the shower leaking, I think they have the experience. Pipes, drains, heat, etc...I'd pick you guys any time; tile, them. There are a huge number of shower pans installed by plumbers that don't meet the national code - they don't leak, but take a poll, most think the liner goes on the floor, and the preslope is all that is needed; not what the code says for a tiled shower.

**PIZ** · 06-08-2006, 12:45 PM

I agree with you jadnashua. I've only posted a few threads on Terry's forum, but each time I received excellent solutions. Most times I have my questions answered just by reading other's threads.

I think what I'm going to do is replace the tiles with a tub/shower wall surround. I never new that I would have to keep sealing the tile grout and I don't need something else to remember. I would probably forget to re-seal it and then be reminded by it when it's dripping on the basement floor or I go crashing through to the basement because the floor rotted out. I think it may be the best solution to just put up a new tub/shower surround. Thanks guys for bringing me to this conclusion.