Possible Shower Pan Cracked?

[TinyHouseDisaster]

Hi all - we have a walk-in shower that was built about 5 years ago as part of an Accessory Dwelling Unit in San Diego. They did a "hot mop" on the shower and it was inspected/signed off by the city prior to the tile being installed. We are now seeing signs of water damage on the wall opposite the shower where the wood floors are and the baseboards (buckling wood floors, bowing baseboards). We called a plumber and they did a test where they plugged the shower drain and filled it up about 3 inches and marked the water line to see if it would go down. The water went down almost 3/4" overnight.

My question is: Does this one test for sure indicate that it is the shower pan/hot mop that has failed or could there be anything else we should test for prior to the very large job of ripping out the tile and redoing the shower pan and hot mop all over again to fix it? Thanks in advance for any help/advice.

PS: I only have a couple of pictures of the construction in this area after it rained once but they show a little bit of where the water lines are running.

 

[havasu]

My hot mop specialist guarantees his job for 5 years. How long has it been? Did you use a tightly sealed test plug to determine if the hot mop failed? Is it possible the water leaked around the drain flange?

 

[TinyHouseDisaster]

My hot mop specialist guarantees his job for 5 years. How long has it been? Did you use a tightly sealed test plug to determine if the hot mop failed? Is it possible the water leaked around the drain flange?

Sadly the contractor was licensed but he has disappeared and we are left on our own to fix it. Plus we were told we are past the point of liability in California since it's been just over 5 years now. It is possible the plug test failed...I suppose we could try that again too just to be sure. Thank you.

 

[Geofd]

The area you point out is below the shower valve has anyone removed the trim to see if that ok

 

[MG70]

I won't comment on the hot mop, but based on your second pic, I'd say it would be pretty easy for water go get around that glass panel behind the spiral stairs and run down to the corner below it. Also, was the backer board properly water-
-proofed and silicone applied around the tile floor perimeter and vertical corners of the tiled walls?

Good luck with the fix.

 

[Geofd]

When you test the shower pan use water from another source to flood your shower base,

 

[TinyHouseDisaster]

The area you point out is below the shower valve has anyone removed the trim to see if that ok

No not yet, is it possible that a problem with the valve could be mistaken for a cracked shower pan?

 

[TinyHouseDisaster]

When you test the shower pan use water from another source to flood your shower base,

Oh interesting, why is that?

 

[Geofd]

Because you won't be filling with the shower valve ,I'm curious if anyone has removed the trim to see if that is leaking behind the wall, that's the 1st thing we do when checking for random leaks you haven't ruled out the water piping yet,you also haven't mentioned checking the window for water tightness

 

[TinyHouseDisaster]

Because you won't be filling with the shower valve ,I'm curious if anyone has removed the trim to see if that is leaking behind the wall, that's the 1st thing we do when checking for random leaks you haven't ruled out the water piping yet,you also haven't mentioned checking the window for water tightness

Thank you that's a very good idea. I think we will check the valves next and also do another shower pan test just to make sure the plug they used wasn't loose. I have seen two ways on how they plug the drain when they test the shower pan - 1) with a plug that's inserted and then tightened by hand with a screw type lock (that was the one they used - picture of it here), and then 2) where they insert a rubber ball/balloon type plug and then inflate that with a pump to make it snug/tight. Curious if you have an opinion on either testing method as to which might be more accurate/effective? Thank you!

 

[TinyHouseDisaster]

I won't comment on the hot mop, but based on your second pic, I'd say it would be pretty easy for water go get around that glass panel behind the spiral stairs and run down to the corner below it. Also, was the backer board properly water-
-proofed and silicone applied around the tile floor perimeter and vertical corners of the tiled walls?

Good luck with the fix.

Thank you for the reply. I don't know a lot about what they did during the construction as far as waterproofing. Everything was permitted and I know they had to have the hot mop inspected. The tile person was very good from what we could see and seemed very detailed. I see how it appears like water could get out over the glass but there have never been any signs of that (water streaks on the wall or anything like that). The glass installation seemed to be very on point also - it has a seal all the way around that does not appear to have any breaks/gaps. I mentioned in another post I think we are going to try filling it again for another shower pan test (using water from another source too) just to make sure it wasn't the plug itself that may have been loose (wishful thinking maybe!).

 

[Geofd]

What does the grout look like, I know it's newer but you never know,any loose tiles

 

[TinyHouseDisaster]

What does the grout look like, I know it's newer but you never know,any loose tiles

The grout appears to be OK. I have opened up the walls where the short wall is now and took up the flooring outside the shower to investigate more. I also did another shower pan test myself and this is what happened:

When filling the shower pan I used water from another source (sink). I put the plug in myself this time, the same screw kind as before and made sure it was very tight. This time the water appeared to go down a little bit but at a much slower rate/level than before, very marginal but still maybe about 1/8" to 3/16". While the water sat I could see no visible indications of a clear leak outside the shower pan area other than the one area with the corner called out in the picture w/ the arrow. This corner was moist and I couldn't be sure if it was from before because it was wet for so long or from the shower pan being filled up w/ water. After 24 hours I let the water out and then took a long shower in it and then shortly after all this water came out of the corner on the floor.

What I'm not sure of now is why would this much water come out on the floor when showering if it were a cracked shower pan but it didn't come out when the water was just sitting in there during the test?

I haven't looked at the shower valves yet but agree it would be great to look behind the wall somehow where those valves are. The shower fixture installed was not very expensive (from Home Depot) and it's been acting funny too - for instance the hose part of it hardly has any pressure right now when it's turned on and the water is coming out very weak...

 

[MG70]

Judging from the new pics, there seem to be a number of things wrong with the installation. I don't see a sole plate (bottom plate that sits on the subfloor) supporting the short wall with the glass on top. That same wall supports the studs and weight put on the studs, including backer board, thinset, tiles, and grout. What's supposed to be a solid and waterproof backer board for the tile looks to have a grid pattern with some sort of black caulking or silicone, almost as if it were the back of the tiles themselves, meaning there's a chance the viewable tiles are unsupported. In addition, the sole/bottom plate on the right side of the pic looks to be wet and rotted from previous water damage. Rotted framing does little to support weight. Lastly, there are no nail plates on the studs through which the Pex lines pass and the Pex seems to be pinched between wood members as they disappear on the right. If I were you, I'd hire a known, quality, tile installer to inspect this, but my guess is everything will have to be torn down and rebuilt. Good luck!

 

[TinyHouseDisaster]

Judging from the new pics, there seem to be a number of things wrong with the installation. I don't see a sole plate (bottom plate that sits on the subfloor) supporting the short wall with the glass on top. That same wall supports the studs and weight put on the studs, including backer board, thinset, tiles, and grout. What's supposed to be a solid and waterproof backer board for the tile looks to have a grid pattern with some sort of black caulking or silicone, almost as if it were the back of the tiles themselves, meaning there's a chance the viewable tiles are unsupported. In addition, the sole/bottom plate on the right side of the pic looks to be wet and rotted from previous water damage. Rotted framing does little to support weight. Lastly, there are no nail plates on the studs through which the Pex lines pass and the Pex seems to be pinched between wood members as they disappear on the right. If I were you, I'd hire a known, quality, tile installer to inspect this, but my guess is everything will have to be torn down and rebuilt. Good luck!

Thank you for your reply. I wondered why there was no sole plate there also, I didn't know if they did that intentionally for some reason. The black stuff is tar from the "hot mop" process that they do here in Southern California. On the stair side they had used plywood under the drywall on the lower wall w/ the glass where I opened it up. My guess was the plywood is supposed to protect those PEX lines? The tile installer said he could replace the shower pan and he would go up 12" and redo the whole pan. My concern now is having him do all that but then the actual problem or leak turns out to be coming from the valves and not the pan. Do you know who would be the best person to call to check and see if the valves are leaking - I would assume that would be a plumber but I'm not sure...thank you!

 

[MG70]

To be honest with you, with what you've found so far, my worry is that the tiles/porcelain all around weren't properly installed and run the risk of leaking through perhaps a backerboard that isn't waterproofed. Grout itself isn't waterproof, so the backer board must be waterproof and the finished tile terminate inside the pan (but higher up so as to not wick water up via capillary action). Another risk, though not as serious due to the fact that the tiles aren't very large, is that the installer used the wrong type/quantity/technique, or even trowel notch size, for applying the thinset.

Your concern about the leak coming from the plumbing is valid, especially if the work was performed by the same person, however, if the water is leaking out of the pan, then it means it's just one more problem. If one is careful, they can open holes in drywall (from the back, sides, wherever) to inspect water connections, etc. I recommend using a large hole saw blade (5"-6") attached to an electric drill and drilling Very Slowly, just enough to cut through the drywall near the fixture, and then using a small flashlight, possibly mirror, and phone camera to inspect. By cutting a clean hole on the drywall you'll make it a lot easier for someone to patch it afterwards, maybe even using the same piece. Another option is to cut a square template out of cardboard and use it with a utility or drywall knife to cut open the drywall and make patching back up easier.

I just clicked on your original pic and it looks as if from the back will be hard since it's an exterior wall. I also noticed that the Left hand corner (left of the shower valve) is wet, even though the water drains to the right of the shower valve, so maybe the water is coming from a connection entering from the left (I don't know if that's also an exterior wall). I'm familiar with hot mops but as a DIY working on my own lower-end properties in a state that sees freezing every winter, I avoid water connections on exterior walls and I use pre-made shower bases so as to considerably lower the risk of leaks.

There are many connections on the Pex fixtures, elbows, etc.. If the clamp, crimp, etc. weren't performed correctly, they too can leak. It doesn't just happen at the valve.

Any, quality, handyman or tile installer should be able to diagnose and fix your problems, but those who work mostly with tile will likely do it better.

Good luck!

 

[TinyHouseDisaster]

To be honest with you, with what you've found so far, my worry is that the tiles/porcelain all around weren't properly installed and run the risk of leaking through perhaps a backerboard that isn't waterproofed. Grout itself isn't waterproof, so the backer board must be waterproof and the finished tile terminate inside the pan (but higher up so as to not wick water up via capillary action). Another risk, though not as serious due to the fact that the tiles aren't very large, is that the installer used the wrong type/quantity/technique, or even trowel notch size, for applying the thinset.

Your concern about the leak coming from the plumbing is valid, especially if the work was performed by the same person, however, if the water is leaking out of the pan, then it means it's just one more problem. If one is careful, they can open holes in drywall (from the back, sides, wherever) to inspect water connections, etc. I recommend using a large hole saw blade (5"-6") attached to an electric drill and drilling Very Slowly, just enough to cut through the drywall near the fixture, and then using a small flashlight, possibly mirror, and phone camera to inspect. By cutting a clean hole on the drywall you'll make it a lot easier for someone to patch it afterwards, maybe even using the same piece. Another option is to cut a square template out of cardboard and use it with a utility or drywall knife to cut open the drywall and make patching back up easier.

I just clicked on your original pic and it looks as if from the back will be hard since it's an exterior wall. I also noticed that the Left hand corner (left of the shower valve) is wet, even though the water drains to the right of the shower valve, so maybe the water is coming from a connection entering from the left (I don't know if that's also an exterior wall). I'm familiar with hot mops but as a DIY working on my own lower-end properties in a state that sees freezing every winter, I avoid water connections on exterior walls and I use pre-made shower bases so as to considerably lower the risk of leaks.

There are many connections on the Pex fixtures, elbows, etc.. If the clamp, crimp, etc. weren't performed correctly, they too can leak. It doesn't just happen at the valve.

Any, quality, handyman or tile installer should be able to diagnose and fix your problems, but those who work mostly with tile will likely do it better.

Good luck!

THANK YOU for taking the time much appreciated! Happy new year! I will keep posting updates as I try to solve this mystery.

 

[MG70]

Happy new year to you as well and good luck with the project!