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shower leak help

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Nov 12, 2013, 05:55 PM
shower leak help
Hi -

last weekend I noticed a thin line of water slowly seeping out from the join of the wall and the floor of my shower. This is along a shared apt wall and there is no shower piping along that wall. On the floor above is a kitchen with a pot filler on the and a water line for the ice maker in line with the shower.

I checked the kitchen floor under the counter/fridge and it is dry.
I checked the neighbour's apt with the shared wall and it is dry.
I checked the apt under the bathroom and it is dry.

The lower glass tiles of the shower are discoloured and in general the caulking inside the shower isn't great.

I opened up the caulking at the join and a little more water seeped out after a few hours. It is now dry and has been for 24 hours.

All water appliances on the floor above have been used and no more water is leaking.

My best guess is that the caulking has failed and water collected inside the wall until it broke through the floor join. There is a built-in well above the leak where bath products sit.

All the shower tiles are solid with no soft spots.

I guess I will remove the discoloured 12 x 24 glass tiles and replace which will tell me if the drywall has been compromised. If it isn't am I safe to simply remove and redo all the caulk?

Nov 12, 2013, 08:02 PM
Most people do not realize that tile, grout and even a masonry liner is not waterproof. Even in good condition, water can get behind all these products, build up and cause a leak.

It sounds like you have isolated the problem to this shower. If you are up to removing tile, you will likely find a damaged backer underneath and then a good chance of nothing else but damaged framing. The bad news is that the only long term fix is a complete surround rebuild with a proper liner behind it. Not one of those jobs that you can do half-way.

Then it becomes time to assess your DIY skills. Can you do a shower rebuild or is it wiser to hire it out?

Nov 12, 2013, 09:57 PM
Probably will not DIY this. Not sure if the underlying framework is compromised. (This could be wishful thinking.) Building is six years old, so metal studs I would think.

I guess the only way to be sure is cutting into the thinset and see what going on behind.

The other drag is that the tile is discontinued. Naturally.
Nov 12, 2013, 10:23 PM
A fairly low percentage of residential construction is metal studs - wood is still more common.

One tip on the tile - Don't give up looking if you have checked at either big box stores or retail flooring outlets. Google around your area and look for a REAL tile store. Look for one that's been around for years and years and caters mostly to professionals. Good chance that it will be located in a not-so-good part of town. But, they either will have old tile in stock or can tell you where to find it - if it can be found.

Nov 13, 2013, 08:16 AM
Thanks, Jaybee.

This is an NYC 12 story apt building, so my best guess is metal studs. Could be wrong though.

The glass tiles are Ann Sacks and there may be an old box lying around somewhere. Fortunately, I do have a spare box of six. If I can remove all the old caulking without damaging the existing tiles and replace only what I need I may be okay.

To add to the issue, the shower is at the far corner of a continuous wall of 12" x 24" tiles and enclosed with glass walls which have been siliconed to the wall. Really hoping I don't have to dismantle the entire enclosure.

Correct me if I'm wrong, but the build from inside out should be tile > thinset > waterproof drywall > liner > stud.

Assuming the source of the water is due to failing caulking, can that wp drywall really be compromised?
Nov 13, 2013, 09:39 AM
Originally posted by nic212:

Correct me if I'm wrong, but the build from inside out should be tile > thinset > waterproof drywall > liner > stud.

Assuming the source of the water is due to failing caulking, can that wp drywall really be compromised?

First off - you are probably correct about the metal studs.

Here's the bad news (and probably the reason you have the leak) Water resistant drywall, also called green board or purple board is not suitable as a tile backer in a shower. In fact, it's been against code to use it in a wet area since 2006.

The WR drywall is no longer used for good reason - it's crap. Once you get a leak it turns to mush and migrates outwards from the source of the moisture. If you can determine that you have drywall behind your tile the only long-term repair will be to rebuild the entire shower.

So the correct order of thing from outside in would be: Tile > Thinset > Backerboard > Liner > Studs. The backerboard needs to be a masonry based material like Durock or Hardipanel. The only time a drywall product can still be used here is if it's covered with a surface product like Kerdi. If you use a Kerdi layer you don't even need the liner behind.

The other thing you may likely find is that there is no liner behind the WR drywall. This is simply a case of it not being built correctly - happens a lot as many have assumed in the past that tile makes for a waterproof surface.

Nov 13, 2013, 11:01 AM
Thanks, Jaybee. That's very helpful.

To be honest I have no idea what is behind the thinset. The place was built six years ago using pretty high-end materials, fixtures, etc., so I doubt they skimped on the board for the shower.

But you never know.

I have a GC coming over today to take a look.
Nov 13, 2013, 04:26 PM
Quick update.

GC confirmed my suspicion - faulty caulking. He found a corner that had some play.

To do:
remove glass door
remove lowest two runs of glass tile hoping they can salvage them
check backing board and if needed replace
replace tiles
recaulk entire shower
reinstall door