I want to start off by saying I'm fairly certain this is beyond my expertise to fix, but I've made progress in the diagnosis. I want to be able to speak intelligently to whomever I end up calling.
Title says it all. We noticed (of course) on Thanksgiving. Since then, I'm leaning away from the plumbing I think it's the shower door itself or the tilework under the marble threshold.
Diagnosis so far.
1) only happens when water is running.
2) pointed running water directly at drain for 30 minutes - nothing
3) covered drain and filled stall with 1/2" of water for 60 minutes - nothing
4) Staggered drain cover around expose outside edgse of drain in 15 minute intervals - nothing
5) pointed water at each wall that wasn't the shower door wall - nothing
4) pointed water towards shower door (cascades down door). Water starts to drip through ceiling.
I didn't see any weepholes so I caulked around the shower door threshold. It seemed to help for a few days but now it's leaking again.
Pictures below.
Here are my questions:
1) Anything else you would recommend to diagnose that doesn't' involve cutting an exploratory hole in my kitchen ceiling? I'm moderately certain it has to do with the door but haven't found a smoking gun as of yet.
2) If it is the door, do I call my plumber (installed the plumbing when home was built) or the guy who did the tilework in 2009? I just bought this house three months ago but prior owner (who had home built) gave me receipts and contact info for everything.
3) What's with the rust spots on the marble? I caulked over one towards the center of track but you can still kind of see it. Is it related? I think there might be a hole under the track as before I cauked I saw water being sucked under the track from the marble base.
Standing water to rule out shower stall pan. Notice how drain cover is staggered. I did this all the way around the drain.
Top down of shower stall threshold. Metal track on marble flat base. Tiled on both sides.
Notice the two rust spots.
Another of the threshold. Notice my caulk job on the inside.
Here is where I believe it may be leaking.