They're all on crack. The only way to fix it is to demolish it entirely and start over from the foundation,doing it correctly with a topical waterproofing membrane. Tiling on top of a problem is like the little pig who built the house on sand and it all fell down, It's nuts.

I'm also inclined to think it's nuts, but when I present my disagreement with this idea I'd like to be able to say why. So, why is it a bad idea?

3aps, I remember well your sad saga. I don't know much about tiling, but have you tried posting this dilemma on the John Bridge forum? They will be able to give you concrete reasons why this is such a bad idea.

It seems common sensical to me that tiling over a problem is not solving the problem, but just masking it, and probably making things worse!

I agree with the posters above.

Mongo:

Thank you for the very detailed and helpful response.

I have a few questions:
By "mechanic", do you mean a tile setter?
By tying into the wall's drainage, do you mean taking out first row of wall tiles?

I am not aware of wall drainage. My husband and I know very little about the mechanics of showers.

Thanks!

Yes, "Mechanic" is a (good) tilesetter.

Yes, one generally removes the lower or so row of tiles in order to tie in the pan waterproofing, which needs to extend a way up the walls. It may be possible to do this with Kerdi or Hydroban.

As Raehelen mentioned, you may want to pose your problem at the John Bridge site....

"I am not aware of wall drainage. My husband and I know very little about the mechanics of showers. "

With the issues you've had, you and your hubby will have doctorates in showerology by the time your construction is complete.

Do you remember them painting anything red on the walls prior to tiling?

I might be confusing your shower with another person's shower, or this shower of yours with another shower of yours. I do remember you having difficulty with several of your installations.

If they did paint something red, it was RedGard, a topical waterproofing membrane.

Shower walls typically have some form of water protection on them.

It could be plastic sheeting (6-mil thick polyethylene) or tar paper stapled to the wall studs, then that is covered by cement board, then the tile goes on the cement board. At the bottom of the wall, the poly or tar paper gets lapped over your shower pan membrane.

Other time installers will use a topical membrane. It goes on "top" or on the front face of the cement board. The cement board goes on the walls, then the topical membrane gets applied to the cement board. Then you tile right on the membrane. Topical membranes can be one of several; RedGard, Hydroban, Kerdi, etc.

We have cement board with red guard on top.

"We have cement board with red guard on top."

That does make it a bit easier.

RedGard can be applied on top of existing tile. I'm not a "RedGard guy", so I recommend you call Custom's tech department. They exist for questions just like yours. Tell them your situation and ask it if they approve of RedGard over marble that has been sealed. If you know the type of sealer used, tell them.

Instead of tiling over the marble, I'd still prefer to pull up the marble, repair the sloped mud, then RedGard and re-tile. That would allow you to get your elevations correct for resetting the bottom course of wall tile. If you tile on top of your current tile, do understand the added thickness will raise your floor up, and you'll have to cut down the bottom course of wall tile when you reinstall it.

That might look fine, or it might throw a nice design a bit out of scale.

If your guys no kidding still want to tile over your current tile, I'd like to see them remove the bottom course of wall tile as StoneTech wrote in his previous post. Do it carefully, preserving as best as they can the RedGard that is behind it.

Prep the marble floor and the drain area. I believe in your previous posts they already demoed the floor tile around the drain and some of the mud around the drain.

They could use the RedGard using the "divot method" around the drain.

RedGard the exposed wall, across the floor, and around the divot and the drain ring. Two proper coats will give you a continuous topical membrane.

Fill the divot with mud.

Then tile over the RedGard.

threeapples: "I'd like to hear whether any of you want to weigh in."

We completely retiled our shower in 2002, and we left in the existing tile. The existing floor was, like yours, hexagonal ceramic tile. The previous tile was not leaky, and we decided that we should not introduce a new opportunity for leaks.

We did strip everything on top of the existing floor tile (six or seven decades of use) and apply a layer of Laticrete film (designed for swimming pool installations) over the old floor before we laid down the thinset for the new tile.

I cannot assess how useful this information is for you, but I can attest that our solution worked -- and works.

We have now had 3 total estimates on what it will take to fix our shower floor. All three want to tile on existing tile floor. The latest tile setter thinks the problem may have been caused by clogged weep holes. He and we should put duct tape over the drain, bring buckets of water in from the tub and see if the water goes down through the weep holes. Nobody is concerned the first row of wall tiles will look shorter because of the extra layers on the floor. I'm
At a loss for what to do.

I read your earlier posts and now this thread and my advice is: Tear it Out!

I put great credence to mongoct's educated responses on both threads and my read is this is the best solution. Take it out including the mud bed. Do it yourselves if you have to or hire a conscientious demo laborer. Give your tiler a fresh new start to this floor.

My bathroom reno is still incomplete due to two significant do-overs. Oh, the angst in those decisions! But both times after waffling, over-analyzing, and yes, crying, the final decision to have it torn out and done over brought me a wonderful peace of mind. The financial implications and time commitment are still hard but in the end that sense of peace outweighs it all. I want that peace of mind for you as well.

This post was edited by mmcf on Sat, Jan 4, 14 at 16:09