1) Carefully read the warranty documents that came at closing. Follow the steps explicitly, and with documentation.

2) Consider getting a professional opinion, probably after the builders pet’s evaluate a second time.

3) Locate any pictures of the build in progress.

Can you clarify, the leak from a shower above the master shower?

The house is covered by warranty so I've notified the builder of this warranty repair. I'm concerned with their initial steps to fix the problem so I wanted to make sure I know what to expect and what they should be doing to investigate the leak.

We bought the house after it was built and were not involved during the construction so unfortunately, we don't have any pictures of the construction. For what it's worth, we had an independent inspection done prior to purchase and it indicated high quality construction overall.

To clarify the leak location, the master bathroom is on the 2nd floor and water leaked through to the first floor. I was referring to the ceiling over the first floor that is underneath the master bathroom on the 2nd floor.

Is there an access panel on the other side of the shower with the pipes so the plumbing can be inspected? Maybe something wrong there. Also, I've discovered that it's really a plus to have easy access to that plumbing anyway.

More likely problem with waterproofing shower. I can imagine that a little bit a caulk is really a fix, maybe a temporary fix at best. Can you get someone, hire someone to remove a piece of ceiling drywall? It would be worth the expense to do it/pay for it so water damage can be looked at......do save the water stained drywall, take lots of pictures and print them out, in case your phone loses pictures somehow. Start documenting all phone calls. Send a certified letter to builder regarding problems along with picture, keep copy of course. Don't rely on texted or emails. Send it in writing by mail, certified. Then they will know you are serious.

Waterproofing a shower like that is very, very meticulous if you want no leaks, especially the connection between the walls and floor, and the floor and drain. You'd be amazed at some of the jokers builders get to install stuff like this. I'd bet anything the floor of the shower was not done correctly. It could be something else, but that is probably the main suspect.

If I'm right, it's likely a tear-out and start from scratch. Whole thing, to the studs. If you are incredibly lucky there are a couple things that can be done to retroactively fix a bad seal to the drain, but if the whole pan is leaking that is bad news. You can't just caulk a few seams and cross your fingers. Like others have said, document everything, and get someone else in to evaluate it and take pictures.

Diagnosis attempt #1 should involve cutting out the ceiling of the room below the shower. Drywall isn’t difficult to repair, and you d as breast have to repair that anyway. That lets you view the drain piping. If that doesn’t do it, then add the wall behind the valve and handles. Those are the least invasive and easiest to repair.

Your description of the issue isn’t the clearest to be able to find causation. Keep a log. Be methodical in documenting it all. I’d suggest a battery operated water alarm as part of your sleuthing. Something like:

* Shower allowed to dry out and not used for 7 days

* Valve activated with cold water only and allowed to run for 10 minutes.

* Drain observed during valve flow, and for 20 minutes after.

* Water observed from shower floor, not drain.

Thanks for the feedback and suggestions! I have a couple updates.

This morning after a shower, I noticed a small wet area of tile at the seam where the shower entrance (curb?) meets the floor. (pictures below) Does this indicate a waterproofing issue vs. a valve issue? Or could it be both?

The builder's foreman came by today to investigate the leak. He ran the shower for at least 15 minutes. Water leaked again, but only after the shower had been turned off. An additional wet spot appeared in the ceiling below the shower. I noticed that the wet area of tile in at the shower's entrance got bigger.

The foreman said that a copper pan was used for the shower floor, so he thinks that it's probably an issue with the valves. He is coming back tomorrow with another worker and will open the wall behind the valves to take a look. Should I insist that he also open the ceiling below?

Yes, open the ceiling to get another view of the pan, drain and plumbing...and just perhaps witness marks left by leakage. The ceiling needs replacement anyway.

A way to see if it's a leak on the supply side (a leak in the plumbing inside the wall, from the valve to the shower head) is to unthread the shower head from the shower arm, and loosely thread a 1/2" cap on to the arm.

Crack the valve to allow water to flow and to fill the pipe running from the valve to the cap. When it starts leaking out of the loose cap, tighten the cap. Open the valve fully. This will pressurize the supply side, if there's any leaking in the plumbing behind the wall it should eventually indicate.

Are you in MA? Asking because of the copper pan. Which usually violate code because of how they are fabricated. But which are required often times by MA code. Gotta love that plumber's union. lol

Thanks for the additional comments!

@MongoCT, Yes, we're in MA. Are copper pans not reliable?

Copper pans are flat on the floor. They aren’t bowl shaped. Which leads to saturation of the shower floor. Because literally everywhere else in the world requires a pre slope under the waterproofing so that water flows downhill and doesn’t just sit there going stagnant.

Your issue is complicated by the choice of porous marble. It will absorb and hold water.

UPDATE: The foreman came back with his lead plumber and another worker today. They removed the shower trim to check the valves from inside the shower and didn't see anything so they cut into the wall behind the shower to look at the pipes and valves. They found a leak from a loose connection between the pipes. (It was the pipe that goes to the handheld shower.) The plumber soldered the pipe. They are hoping that this is the fix to the leak.

The team did not open the ceiling to look at the pan, drain, and plumbing since they found the leak in the other location. The foreman agreed to replace the ceiling though.

I'm hopeful, but a couple of things seem odd. The leak happened after almost 6 months of use and the leak is not constant. It's only happened a few times even though we use the shower every day. Once we became aware of it, we noticed that it happens after the shower is turned off. Also, as I mentioned above, I noticed a wet area above the seam in the tiled shower entrance. Today, I noticed another wet area near the previous one and it I noticed it a couple of hours after the shower had been turned off (and after work had been done on the shower).

Here are pictures of the plumbing and the new wet spot on the tile.

Did you see the leak that they fixed. Did you see it actually leaking? How much, just a few drips? Would it have been enough to have water get to ceiling below. If was the easiest and cheapest fix for a leak. Hopefully that is it. Can you have them take a section of the ceiling out and not immediately close it back up. So you can observe if anymore leaking going on, including area where pipes were exposed, also give it a chance bro dry out really well. I hate the idea of enclosing with moisture still present. Have them close it back up after a couple of weeks or so.

I am suspicious of something you said in your original post and am surprised more qualified people did not point out. The tilers should not use grout in the corners, ie; from floor to wall seam, in corners etc, changes in plains, should only use caulking there. Did they remove grout and replace with caulk or did the they remove caulk and replace with new caulk. Although, it should not leak around tiling job just because some faulty caulk or grout job.

I don't like that wet looking spot on the curb either.

@Izzy Mn Sorry for the slow reply. I did see the leak and it seemed like just a few drips. It did not look like something that would lead to the amount of water that came out after a shower. I'm wondering whether water is holding in the pan of the shower and then overflowing, but then how would that be related to the slow drip leak from the pipe? One thing is that the connecting pipe that had a leak goes to the handheld shower and we don't use it very frequently. So far, we haven't seen additional leaks yet. The wet spot on the curb doesn't always appear, but I'm continuing to watch it.

Regarding the caulk vs. grout, the tile guy is going to come back once the leak issue appears to be resolved to remove the grout and replace with caulk. I'm not sure what was used when they tried to fix the leak the first time, but it was the wrong color and there was too much of it.

I know this thread is old but have had similar issues. did their fix clear up your issue or has it still happened since?

@riellebee Forgive me for resurrecting your past pain, but the industry is working on education for homeowners about leaky showers and your photo of the water on outside of curb could be useful. Would you be willing to grant permission to use? Photo only, no personal info. Thanks!