your absolute best bet is to steer clear of bad info on this site !

Call Schluter 1-800. request a rep comes and looks at your schluter system shower. Maybe theres a chance said REP knows the installers .....

you need facts from MFG.

Jeff, how do we know OP didn't ask questions? How do we know the designer didn't inform them? (but based on her reply to this issue, I'm betting she's clueless)

some people just want marble, regardless. In this day and age, a homeowner ought to know that marble is fragile. A good designer would have said something, but again, maybe she did.

Doug, you're saying they used a Schluter system but you have no pictures?

do we know if any leak test was done?

is the shower pan sloped properly?

how the drain was done? weep holes aren't covered?

This could also be a cause. But from what the pictures show, the marble is absorbing water.

You can see the white part toward the front that doesn't get much water, compared to the back portion that gets all the water.

put a 3' level at 12,3,6,9 oclock, and see how the floor is sloped

If there is no sealer on that tile, or not enough, water will leach through like nobody's business.

let it dry out completely, apply a good sealer (call in a pro) and see if that works.

Of course contact Schluter and see what they say.

Have you questioned your installer? don't know why the designer would know anything.

MInt Tile, exactly what bad info did I give? it's obvious the marble isn't sealed properly. Those aren't stains from products, it's from water. I suspect it's the marble and the substrate beneath it, but they said they had a Schluter shower system, and without further pics, we can't automatically assume they did it wrong.

Occams razor. I'll go with the most suspect first until something else is proven amiss.

@Beth H. :yes lots of responsibility to share around, but i think the pros should take the majority of it. unless the client was told about the issues with marble and simply demanded it.

We were not told that we needed to seal the tile 3-4 times before use. The invoice from the designer specified that this tile had been waterproofed (see attached). She selected the material and hired the installer. Neither of whom alerted us to any additional maintenance before installation, nor did they inform us of marble care after installation/before first uses.

I regret not asking more questions but felt we were only signing off on the design/aesthetics and that she and the installer were making wise choices of material to use for a shower design.

We were given special tile cleaner to use and have only used that product since day 1.

Here is feedback the designer collected from a few of the reps:

Schluter Regional Rep

I called the regional rep for Schluter in our territory and shared images with him, asked if there was anything we should look for to trouble shoot this issue. He said there are many variables with natural stone and setting materials, but emphasized that bird bathing would not be possible with Schluter shower system, he still recommended we check the surface level as variables could include thickness of marble mosaic and differences in thickness of mortar underneath the tile (installer checked surface of shower floor with a level and all was flush, I would agree that this rules out the possibility).

When one installs a Schluter system tile, is water NOT expected to get under the tile? (I'm asking because I really don't know.)

Mapei Regional Rep (Setting Material Manufacturer)

Shared images with Mapei’s rep who recognized this as moisture right away, said he sees this in Schluter shower systems frequently with natural stone shower floors. He recommended sealing with a water based penetrating sealer, but emphasized that with porous material water will always find a way. As to why moisture is pooling in those two spots he said there could be any number of reasons preventing water from flowing as expected.

We would recommend not using the shower for 2-3 weeks to allow the water to evaporate, and then using Mapei’s UltraCare Penetrating Plus Stone, Tile & Grout Sealer. I understand that we tried this before in combination with a stain remover, I would like to confirm that this stain goes away without the stain remover (I suppose that if it doesn’t it may confirm that there was something else causing the stain, I just can’t imagine what this would be since the stains reappeared in the same spots and all persons consulted believe this to be moisture). I should note, however, sometimes people are known to urinate in the shower. This could cause certain areas to absorb the urine and appear differently than the rest of the floor tile. We would always recommend marble to be sealed especially in wet areas. We do not believe this to be a defect with any material or an issue with any factor of installation, tearing out the stained sections would only compromise the waterproofing of the Schluter Shower system and add more variables into the install as a whole.

Hamilton Parker Technical Services Manager

I shared images and spoke with our Technical Services Manager who said images were classic water trapping as we would see when bird bathing occurs in a poured mud bed of a shower floor (Bird Bath occurs when there is a slight low spot in the substrate, causing moisture to pool and not flow unimpeded to the drain). We do not sell Schluter Shower Systems, but this surprised him since a bird bath should be impossible with this product.

This is all we have ever used on that flooring.

It doesn't look like you peed on it or otherwise mistreated it. It just looks wet.

Can you believe they said it could be urine?! How humiliating. 😳

Doug, that's exactly what my concerns were. that's why I asked about the shower pan construction, leveling, and is it draining properly. (weep holes sometimes get plugged around the drain).

when he put the level on and all "is flush", I do hope you have a slope to the drain. should be 1/4" for every foot. The shower pan should have also been constructed w/a slope.

Since you don't have pictures, we don't know if any of this was done.

Staining. White marble will stain w/colored hair products. or if someone dyes their hair and it washes over the stone. (if it's properly sealed, this shouldn't happen unless someone is pouring koolaid over the tile for 15 solid minutes) But if the water is not draining properly, then any staining material can have a chance to sit on the surface longer and possibly stain the marble. with a good sealer, it really shouldn't be an issue since you could get anywhere from 30mins to a few hours of stain protection before it sets.

It looks to me like the stone is absorbing a lot of water, and it's sitting under those 'low' spots, unable to completely drain away.

When you sprinkle water on your stone, what happens to it? does it sit or absorb after 5 mins?

a sealer won't make tile waterproof, but it will slow down most of the absorption (depending on the sealer). that's why I mentioned mine. water literally beads up on the surface and just sits there.

(oh, and urine is acidic and you'll have etching marks!! is it etched?? then it's prob not urine)

I'm going out on a limb and saying those sealing products are not good enough. never heard of them. That's not the impregnating sealer to use for stone in shower.

You need 511, Aquamix, or something like the one I pictured

sealer is applied, you wait a few minutes, and buff off. always test on a sample piece. when water beads on the surface, it's sealed.

In different areas it responds differently. Where there hasn’t been any staining, the water sits on top for five mins. Where staining has occurred, the water absorbed.

This is with the largest level I have at the moment.

Where there hasn’t been any staining, the water sits on top for five mins. Where staining has occurred, the water absorbed.

Well there ya go.

get yourself a top quality sealer

(do the walls too)

the bubble on the level really jumps as you get close to the drain. maybe excess water is pooling around that spot.

of course if the stone was properly sealed, you wouldn't get the amount of water, so, there's that.

looking close at your pics around the drain, the grout job seems to be less than ideal. horrible clean up.

If this was mine, I'd wait until all the water has evaporated (put a large fan on the tile) and then I'd call in a marble restoration guy. He will refinish all of that tile and sand off any remaining grout (it seriously looks very rough and pitted. Do you know if they use Unsanded grout?)

After it's repolished (or maybe you want it honed instead) he will apply a really good sealer like that Protex. (or he should) cost for redoing the floor would be in the 300-500 range.

Fantastic Beth!! Thanks for all the information. This thread has been so helpful and I greatly appreciate all the input.

doug, I edited my comment and added a few more sentences.

You can't pee on a marble shower floor?

Absolutely the best reason yet not to use marble.

carrie, you can if it's sealed ;) (but try and aim for the drain)

The best prep in our opinion for a shower floor with natural stone is a mud pan (dry pack system/water in, water out). Proven method by a QUALIFIED CRAFTSPERSON. Sorry and with much respect for the varied advisers. Here's the deal. Marble is and has been used for centuries in showers with a very long life span. The recent (last decade) concerns primarily relate to changes in manufactured tile prep systems and products (in this case, for wet applications) including foam pans, setting materials, and lesser quality stone (all these come into play). These setting material products and systems can be acceptable but they have proved to require very specific installation procedures for use with marble. Your tile installer needs both information and experience with the products being used specific to marble installations.

In your case we question positive pitch from perimeter to drain at consistent plane as one factor. Importantly, the advice on sealing the marble should be specific to the system used and per manufacturer recommendations. Sealing is not the "answer" and in some cases not advised for specific installation systems SO BE CAREFUL about the advice above about sealing. We have installed, and will continue, many marble showers over many decades, free of the problems mentioned. Hire wisely. Recommend you research and share with your installer the following. Research to more from Pasha about installation with foam pan systems (where there are different recommendations). OR hire an industry professional with knowledge of all these methods and the experience to provide you with a lasting marble shower installation. https://tilepro-usa.com/tile-pro-blog/f/eliminating-marble-moisture-discoloration?fbclid=IwAR3v8Z1QbZsL505M207noqJP7UDJ3HUKEdl5WCuHd2ZOLs4rF50UGBaK5sA

It looks like bird baths, and you absolutely CAN have bird baths with a kerdi shower. Sealing will NOT prevent etching (this pertains to the above comment about using sealer to prevent etching from urine). Using a level won't detect what's going on underneath the tile. The tile can appear flat, without dips, but that doesn't mean the mud bed underneath is flat and without dips and craters. It's those dips and craters that are holding the water, preventing it from making its way to the drain. Using sealer can actually exacerbate the problem by slowing down the rate of evaporation of the water back out through the tile and grout.

catbuilder, I never said a sealer prevents etching. They were talking about staining, urine stains. Read further up and you'll see the comment. (that's why when she said, "you can't pee in a marble shower?" I replied like I did, and trying to be humerous. There was never any mention of etching.

I'm well aware that sealers don't stop etching. I have marble everywhere in my house. I already said in my earlier comment that sealing won't prevent etching and to be careful w/any acidic cleaners.

I get what you're saying about the sealer causing a slow evaporation. or maybe it would work the other way. It's a catch 22.

Sealers don't make a tile waterproof or stop gas exchange. Sealers give you time to wipe up any materials that might stain before it sets in the stone. They will make the tile water resistant, but it's still going to absorb.

Doug, and others, the one thing no one knows is the shower bed. Yes, it could have dips and divots.

For all we know they could have said they used Schluter, charged him for Schluter, and used something else. Or the installer could have royally f ed it up! None of this is known.

Everyone has their own take on this. "use a sealer, don't use a sealer". Well, you see where NOT using a sealer has gotten you! This is known.

But, If using a sealer "exacerbates the problem by slowing down the rate of evaporation of the water back out through the tile and grout", and not using a sealer causes the tile to absorb like sponge and never drying out,, then what is the answer?!

If the sealed portion of the shower are the parts w/no darkened stains, then maybe it's worth trying on the un-sealed portions.

Because lets face it, the only remedy after trying that is to rip up the shower floor and redo it. (and if this is one entire waterproofing system, that may not be possible without doing all the walls too.)

Doug, you paid a grip of money to have this done. For that price you shouldn't have to deal w/this.

I think the tile installer should have some responsibility in this mess. How do we know it's not his (or whomever constructed the shower bed) error?

Dragonfly, thanks for adding that. I mentioned sealing the tile because the portions of the floor that are not stained are the parts that OP said water beads up (the part that took the sealer). the portion of the floor w/all the wet stain marks are where he said the water does not bead, but gets absorbed.

I have a marble shower floor. built it w/the old school mortar bed and hot mop. I haven't had one issue with it. also have the mud walls. maybe old school shouldn't be overlooked.

I'm trying to start w/the most obvious, easiest solution. OP has contacted Schluter and Mapei and they both have advised the same thing. Short of ripping out the floor tile to see if the shower bed is wonky, I think it's the best solution.

Just because they bought the schulter system does not mean they used it properly that is water under the tile all the sealing in the world will not help this it was a poor install, period.

I think it's interesting that the pictures from the johnbridge forums tend to have the staining concentrated around the drain. This would suggest to me that water is sitting in that low spot and not completely draining. The OP seems to have staining all over the floor so maybe there are multiple low spots. Does the staining occur as much in "water in water out" systems. Perhaps the modern sealed systems hold water against the marble for longer and the staining occurs, although the reason for low spots on a foam floor must be careless installation. Maybe it's down to inexpensive marble being used for the mosaics. Bottom line is to be safe I would never use something as porous and variable as marble in a shower.

FYI I have a shower with a mud floor covered with Hydroban and 2" hex porcelain tile. The grout around the drain is always the last to dry out, but the tiles obviously don't get stained or water logged. I think marble just really highlights low spots in a shower that would go unnoticed if a porcelain tile was used.

@Jeff Meeks I know we think if we hire an "expert" they should tell us everything we need to know but unfortunately that is rarely the case. Where I worked I dealt with contractors and designers all day long. I had designers like Beth who know their stuff and did their job well. I also had designers who didn't know the difference between using porcelain and using marble. I had designers who didn't know the difference between quartz and quartzite. I had contractors who couldn't install a schluter and would send their customers back to pick tile that had a bullnose. Bottom line is the buyer should be educated and not just blindly trust the "expert." I cannot tell you the number of customers who came into our store and said their contractors told them to pick out some marble and once I explained the care needed, they changed their minds in a minute.

@Lisa, sure I agree. Projects usually fail when a number of errors compound and people don't catch them, but still I put more blame on the professionals than the client.

It's a Kerdi drain, so most likely they used Kerdi. In any case, a topical waterproofing method was used. A shower with a topical membrane will dry out faster than one with the old-school method of preslope/liner/mud bed. The mud bed in the old-school method can stay saturated, so the floor would be uniformly dark from the absorbed moisture. Hence, you probably wouldn't even realize that the marble was darkened from the moisture. The blotchiness occurs in the kerdi shower because it is caused by dips in the mud bed, which the membrane conforms to. The water in those dips has no way to drain (because it's caught in a sort of bowl), and it can't percolate through the mud bed (like it does in an old-school shower), so its only way out is through evaporation. As you can imagine, that evaporation can take quite a while.

History should never be discounted. Why did it work in the past? Our answers are often in yesterday and what we learned to be tried and true.

So what should be done? Who is responsible? I paid an large amount of money and am not satisfied with the end result. Am I stuck with this?

Mint:

You are always quick to discount what others have said, but you rarely offer a reason as to why the other poster is wrong and how to fix the problem properly.

Youve pulled your act again.

Please analyze the OP's problem and let us know how to fix it.

Thanks.

This is not difficult IMO.

1) Put a long level across the areas that show the staining. If you see dips then the install is bad and the contractor is to blame. The level should lay flat on the tile with a pitch towards the drain of 1/4" per foot. If you can see light between the level and the tile then that's a dip and water will sit in it.

2) If the tile is all correctly pitched towards the drain then is is probably just a bad material choice and the professionals should have known better. I'm an amateur and even I know that using natural stone products in a shower is risky and best avoided. I would bet that the marble used for mosaic tile is not the best quality and will be very variable from batch to batch. As the client you also have some responsibility to do your own research, just not nearly as much as the professionals.

3) Live with it or tear it out. I don't think you'll have much joy trying to fix it with potions and sealers.

@Jeff Meeks, "and even I know that using natural stone products in a shower is risky and best avoided" UNLESS you have a craftsperson who is experienced and knowledgable about the products and methods.

@Dragonfly Tile & Stone Works, Inc.

People certainly like the classic look and idea of marble so maybe your could give them an idea of how to assess a craftsperson and their recommendations. So how should we be specifying materials ie marble and thinset, what installation techniques and methods should be used ie water in and out vs sealed systems, what surface treatments should be used once installed. Does the water quality matter and should that be a factor? What questions should the OP have asked and what are the right answers?

I have read the very useful and detailed links you provided in previous posts and the installation of marble successfully in a shower is not a straight forward process and really I would simply avoid marble in showers simply to mitigate risk

@Jeff Meeks, " I would simply avoid marble in showers ..mitigate the risk". And that's sadly what's happening for multiple reasons. This is going to be lengthy so hang with me. I have utmost respect for the craftsperson who says "no, I won't install that", because they are owning their comfort, assessing their own risks based on what they know and their experience and want to provide a trouble-free install. And that's a good thing. The back story: Marble showers have been around and thriving for centuries. Problems started occurring with the introduction of all sorts of new materials and methods as well as a less trained workforce and the introduction of lesser quality marble from various sources. That is a fact. With the new materials/methods comes $ for manufacturers, liability ($) for the installers and suppliers. Why do you think suppliers will sometimes advise against marble in showers? They do not want the liability as they can't control the installation. We are calling it here like it is in our opinion, and it's even a bit political within the industry for these reasons but I'm too old to care about that and more interested in preserving the beauty of natural stone products and craftsmanship. I've referred to Pasha on multiple posts because he took the time to really research. The old "water in/water out" mud pan system, done correctly, is our standard for marble shower pan installs. Further testing is being done for foam pans but in my opinion, we're not there yet. The good news is that the research is being done with the various systems AND the industry is seeing a keen interest in old school mud systems. The badgering back and forth in the industry "mud verses foam" is a common thing. At this writing, there is a group of installers landing in Nebraska for an industry sponsored "Mud Event". Installers that want to learn these methods. There are more scheduled by the professional industry throughout the year and the "younger contractors" are realizing the importance of learning these methods for so many reasons. There's even a group of women installers planning their attendance at a Mud Event" in Idaho in a few months (they are referring to it as "Dirty Girls Meet"). And so, there is hope that the old school methods will continue to be taught. And the newer technologies will continue to be researched for best practices in marble installations.

To answer your question:.... If you've referred to the "13 Questions to Ask" (when hiring a tile contractor) you will note that it is important to ask about their experience with the materials you want to use, their training and their involvement in the industry. IN ADDITION to all those questions the industry has laid out, I would ask specifically (if marble was the choice):

Do you use a mud pan system for your marble showers? How long have you been doing them and how many have you done (and can I speak to previous clients)? What other manufacturer products do you use and why? What do you think about THIS marble (sample) and any concerns with quality? I've seen MANY quality marble shower installs shared by industry professional colleagues just in the past few weeks. Qualified craftsmanship. Let's not cancel it or the historically beautiful products.

Hope this helps.

@Dragonfly Tile & Stone Works, Inc.

Your post is detailed and informative and should be a must read for anyone wanting a marble shower. However, I think your list of questions and recommendations is going to filter out a lot of otherwise capable contractors and shower builders who are more familiar with the modern sealed systems. So if marble is really and truly want is wanted then there's going to be a fair amount of time and knowledge required to assess the contractors up front and the client will have to pick from a smaller pool of professionals.

@Jeff Meeks Yes, you are correct sir. It may filter out otherwise capable contractors. If you need specialty plaster work, you will need to do the same. It's true with all the trades.

I didn’t hire the contractor, the designer did. I hired the designer as the expert to execute an aesthetic. I didn’t ask for marble. I was’t even fully aware it was marble until she provided an estimate at which point I assumed this was a vetted and recommended material for use in a shower.

Needless to say, I don’t have the aesthetic I paid for and no one is helping to remedy this eyesore.

I suppose we will pay the ten’s of thousands to have this replaced by another professional with a different material.

This is what I approved. It says “shower tile”. Why would I assume there would be issue with this tile in a shower. I feel dupped and left holding the bag on a terrible material selection/potential shoddy install.

Doug, the "designer" specified the material and hired the sub-contractor. The designer is responsible perhaps, without seeing your contract. Did you pay her/him (designer) for the tile work?

Yes, payment for the design, materials and installation was paid directly to the designer.

Doug Brown, Sorry if you've answered this but what does the designer (who has acted as a General Contractor), say about this?

In October, it was assumed to be a stain we caused with hair and body products. So we were instructed to attempt to lift the stain with marble stain removers and let it dry out. Once the stain was lifted, we resumed use of the shower and the stains reappeared. (Which of course they did, it never was a “stain”, it’s waterlogged tiles).

When the tile discoloration came back they said to let it dry out again and they’d try sealing it. But the contractor is “too busy” and can’t come out to seal it for several weeks. We haven’t been able to use our shower for over a month and it could be another month before the contractor comes out to seal the tile.

This same contractor did the backsplash in our kitchen. It’s cracked everywhere.

@Doug Brown The joint between the backsplash and the counter is cracked because it was grouted. The rule is that at changes of plane you use caulking on the joints as it is flexible and gives with movement between the perpendicular surfaces. Grout companies have color matched caulking for this.

Yes, that’s what my google search results yielded as well. I feel an expert tile installer should know this. Could be why we are also having issues with our marble tile shower floor. Perhaps, this is not an expert installer after all.

@Doug Brown I think there are plenty of skilled people out there who have learned the trade and basically stopped learning as soon as they are set up and doing jobs. They do things their way and don't keep up with TCNA or evolving best practices. Then there are also plenty of just bad people with no professional pride looking to take your money.

Finding the skilled professionals through the mass of self proclaimed professionals with a Facebook page representing their “professional business” is beginning to feel like finding a needle in a haystack. 😔

I think a TCNA accreditation is a good starting point. With plumbers and electricians in my locality it's hard to find a bad one because the trades are so highly regulated and inspected. You can weed out the bad ones by asking to see the permits and inspections. For tile and shower work it's not as easy.

I have a contractor who's done good work for me over the years and I hired him to do a more major renovation involving bathrooms and a shower. His tile sub installed showers using the a copper pan (very common where I live) and mud floor and the old CBU and plastic sheeting method. I wanted a sealed system so we went with Hydroban and I supervised the installation. The tile guy was very patient with me and did a good job. I also suggested an uncoupling membrane on the bathroom floor and he did that. He said clients were asking for that a lot now, but it still wasn't his default thing to do. He was an older guy and did nice work, but it was probably state of the art for the 1980s...

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