redoing a shower floor

RNTeare · 11-21-2009, 02:52 PM

My tile layer screwed up the pitch leading water down to the drainhole. He did it freehand instead of using a straight edge. The floor is "cupped" and does not drain fully.
He proposes to lay a new layer of tile on top of the old, correcting the little bit of cupping.
My questions are: does one have to take out the oldl tilel to do it right? If so, does all the mastic glue have to come out. Does the concrete that has the "cup" in it have to come out, or can it be fixed with a scim coat? Will it look funny on the walls if we just put new tile over the old?
Thanks for all thoughts on this.

RNTeare

Mop in Hand · 11-22-2009, 01:21 AM

Mastic Glue? What was used exactly?

Bob Mariani · 11-22-2009, 07:16 AM

Take it all out. I hope he did not use mastic and used thinset at least. If you have a puddle then he most likely did many many things wrong. There are many critical details on how to do this and a flat and correct slope is not one of the harder issues to deal with. Read articles on the schulter website on how this is to be done. Buy and use their products to make it a DIY job that can be done right. Hire a better tile setter, this one is a joke.

RNTeare · 11-22-2009, 10:23 AM

Thanks to Bob Mariani for getting back to me so quickly. I am pretty sure, now, that my tile guy used only thinset (concrete) right under the tile. I never saw him use a screed board, for goodness sake. (Even I know that much.)
I looked up the Schulter system. Quite elaborate. I have now, installed, PVC drain materials and waterproof liner most probably from Home Depot.

So, another question, trying to stave off expense and labor: can we not get a fully adequate (I know these are fudge words.) shower by removing the present, "cupped" tile, then getting the slope right by using a screed board, and then (I think.) waiting for that to dry. Then putting another very thin coat of thinset to bond the tile. And then installing new tile on that final coat of wet thinset?
I am hoping.
I should add: I am in Florida and have received almost always good workmanship from the guys we have hired. So, we are quite disappointed to have to go through a number of steps to get our shower back in working order.
RN Teare

Bob Mariani · 11-22-2009, 10:30 AM

you can attempt to patch the floor. it will work IF... the waterproofing membrane was done correctly to start with. Most likely it was not. So you are adding more costs and time to something that will fail in a few years.

ccarlisle · 11-22-2009, 10:33 AM

Nope. What you are overlooking is water management ie. how do you make the water run down the floor tiles and into the drain. For that you need a membrane not just a slope. That's the beauty of the Schluter system and makes it almost DIY: the management of: the slope and the water runoff and the drain.

RNTeare · 11-22-2009, 04:28 PM

Thanks all for your information. I have much more confidence now in thinnking I know what I am doing. I believe the waterproof membrane was put in correctly, and that when a correct slope is established, I will be OK. I read about the Schluter system and see that it is significantly superior to what I am doing, but I do want to reinvest in a new system, that is, another three grand at least.
Thanks again.

RNTeare

ccarlisle · 11-22-2009, 06:09 PM

OK then, but I'll tell you the sloped mortarbed and the membrane may be there but it has to be properly hooked up to the drain to make it work and not leak. OK, same thing for the Schluter - or any other - system but it's a wee bit complicated with the membrane and the weep holes etc. FYI the whole Schluter shower kit (floor, membrane, shower base and drain) sufficient to do the whole shower costs about $500...it's almost DIY!

There is lots and lots of online information about showers and how to build them; it's quite impressive how many details and mistakes can crop up in one small enclosure.

Good luck; just keep coming here for answers.