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06-20-2019, 07:23 PM
Bathroom remodel with many mistakes by tile subcontractors-- GC willing to fix them--if I tell him which ones. In the interests of time (8 weeks now with no shower) and reasonability, I would be so grateful for your opinions on which mistakes you would let slide and which you would have fixed. All of the products are Schluter. Mistakes = not pursuant to Schluter installation instructions as I read them.

Bathroom floor - Schluter all-set, ditra heat
Shower (formerly closet) - Kerdi board, kerdi-line drain, ditra heat flooring

1) the ditra heat cable was run between the wall and bathtub, a 3" space. The cable will be under the outer edge of the bathtub, just barely

2) In the shower, the kerdi-board seams and all corners are covered with lots of Kerdi-fix, not kerdi-band

3) In the shower, the screws are also covered with kerdi-fix, not kerdi-band

4) shower floor layers - plywood, Schluter all-set, ditra heat, mapei ultraflor modified thin-set mortar (should I have them replace the mapei with the all-set)

5) ditra heat cable is not embedded in matting around the kerdi-line drain, it is placed on kerdi-membrane on the sides of the drain (the drain is at the entrance of the shower and not much room for the matting on the sides)

6) the kerdi-line drain channel is fit into a rectangle hole of the same size in the subfloor. it is connected to plumbing and just the edges of the channel are mortared to the sides of the subfloor. (GC wants to know how I want this to be fixed)

7) the shower floor is higher than the bathroom floor on the other side of the kerdi-line drain

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06-21-2019, 07:19 AM
With respect to the Kerdifix used as an all purpose goo:

Kerdifix is NOT approved to be used as waterproofing sealant. Think of it as a glue, that MAY seal water, but it also might leak.

It is used to adhere kerdiboard to things and adhere kerdi to things. The waterproofing is always supposed to be from overlapping kerdi membrane with an approved thinset as the bonding agent of the two membranes.

Will his method work? In my minimal experience, probably, BUT I have seen examples where water still wicks through in applications such as yours. You may be safe in a wall, as the examples of leaks I have seen were on the floor. Nevertheless, Schluter would call your installation erroneous and not warranty it, if you ever tried. While the GC may say HE will warranty it, you won't know if you have a small leak for months or even years, depending on the size, how often it is used, etc.

Not sure how to fix it without creating a big speed bump. We would have to see just how much kerdifix was used. Are you sure it was ACTUAL kerdifix? That stuff is expensive, would not surprise me if he used some other random sealant.

With respect to the questions on the linear drain and dirtra heat, I do not know. I have never used either.

06-21-2019, 09:26 AM
#1 is it the actual heating portion of the cable? Or the unheated lead? The shaded portion is supposed to be 2 in away from cabinets I think they worry if it's in too much of a confined area it will overheat. What will be between the cable and the bathtub? did they run it in some kind of Groove to protect it or in ditra heat matting?
I don't think this is a big issue if it won't get crushed and isn't heating portion.
#2 they can just cover the seams with Kerdi band hopefully there's not a hump of Kerdi fix.
#3 I have not used the Kerdi board and screws but I thought covering with kerdi fix was ok
#4 are you saying they want to use ultra modified under your tile?
Or they have used it to fill the voids before tiling? Many people do use a modified between ditra and tile it does not meet the warranty unless it's all set or unmodified.
#5 I guess you're saying in order for the heating cable to get into the shower it has to go across the drain and the membrane is the only place that it can cross so that means ( the drain picked was to long) it will not be protected very much but as long as your thin set is 1/4" thick it should be okay as long as it's protected during the tiling process but you may want to call schluter about this.
#6 so you're saying the flange is just a thickness of thin-set above your subfloor but it's probably well-supported. Obviously they did not use a Kerdi pan so they must plan to slope the floor somehow with a mud-bed? Off which should not be installed thinner than 1/2" 3/4 of an inch or so.
To fix this I guess they would raise it up and set it on the styrofoam that was provided with the drain. This will change the elevations but that's part of the planning process.
#7 if the drain is at the doorway and the floor slopes up away from the drain towards the back of the shower that is how it is supposed to be, a quarter inch per foot.

06-21-2019, 12:16 PM
Thank you for the responses. Mike, there were 8 empty kerdi-fix bottles in the dumpster (yikes). They are re-doing the shower with the kerdi-band where it's supposed to go.
Teddy, thank you we are addressing the heat cables with matting under it all and buried in thin set. They used the mapei thinset in the shower over the ditra-heat and under the kerdi-membrane. It voids the warranty but so does everything else in there, so if it works and it's only this one part I'll deal with it. We will see what happens with the drain...
Thanks again I really appreciate it.

06-21-2019, 03:33 PM
Kerdifix IS waterproof. It's a very expensive way to seal joints and screw penetrations. It's the way Wedi does it with a very similar product. I think if you call Schluter, they'll tell you it will work IF there's a continuous coverage. How much overlap they want, I don't remember. One of the instructors said he patched the vinyl liner of his pool with it underwater, without draining his pool. He did use it as the adhesive to hold a vinyl patch in place.

Kerdiband is the much less expensive way to get a waterproof seam. ON a tub/wall junction, their videos show them using a bead of Kerdifix to adhere a strip of Kerdiband to the tub, and thinset to hold it onto the wall, whether that's Kerdiboard or Kerdi.

06-21-2019, 04:05 PM
If you watch Schluter's video, you'll notice that nowhere do they advertise it as a regular bonding agent between sheets of Kerdi. Seems though that they do approve installations done that way upon request.

It might also be of interest to check out the video posted here:

I think the regular thinset plus Kerdiband / Kerdi method that includes the 2 inch overlap is the cheapest and best way to proceed. That's how the system is designed to work. Some Kerdifix in critical spots can't harm if deemed necessary but shouldn't be required. I am a believer in the system and am happy with my two Kerdi showers.

06-21-2019, 08:30 PM
Welcome, Kate. :)Bathroom remodel with many mistakes by tile subcontractors-- GC willing to fix them--if I tell him which ones.You should not be required to point out those areas where manufacturer's recommendations were not followed by your GC's subcontractor, your GC should be showing you how his work meets the manufacturer's requirements. It is his responsibility to correct each and every situation where that is not the case. Following product manufacturer's instructions when installing their products is required by building code.

Your GC knows that, or certainly should. A simple suggestion from you that his tile sub isn't following Schluter's installation instructions should be more than enough input from you to get it all corrected or sufficiently explained to you.

My opinion; worth price charged.

06-22-2019, 06:39 AM
CX,. It's 2019! You live on planet Earth. System Update needed. Haha.

Kate,. You didn't say what type of material was used to make the slope in the shower? I didn't know the highly modified thinset was used to put on kerdie over the ditra heat. Using highly modified between these layers ( kerdi so large compared to any tile) really has prevented air from reacting with the thinset. I would call mapai about that exact thinset. Mapai also makes unmodified thinsets.
However the drainage bed concerns me the most out of all your issues. If you have slope at all it means some material tapers down to next to nothing at the drain. I'm assuming the drain is on a very thin layer of thinset so maybe 1/4 inch above the subfloor. This junction is not very strong. of course we do not know how that subfloor cutout was supported or how strong your subfloor is. I will feel better if you tell me it was cement but I think you said it was plywood. The flexing right around the drain could cause an issue with the membrane

06-22-2019, 08:31 AM
Teddy, the standards of responsibility in the homebuilding industry do not vary with the competence and reliability of the contractors involved. A General Contractor has a fiduciary responsibility to his customers, regardless who is doing the actual work on the project. I don't believe any "System Update" is needed in that arena, thank you.

06-22-2019, 09:46 AM
I am old-school quality and it's very depressing living with the craftsmanship of workers today. I just don't know how many GC are going to rip up a floor and redo things. At a minimum it's like pushing a rope up the hill and not a good experience in life. For the workers many times doing things the wrong way pays more by the hour.

Dave Gobis
06-22-2019, 10:00 AM
As someone who deals with claims daily for a living, I can state unquestionably it is wrong to assume a GC knows what should and shouldn't happen in sub trades categories.

06-22-2019, 12:23 PM
Point taken, Dave, but I still submit that he knows he is responsible for any deficiencies in the work performed.

Teddy, I understand and share your position on the available quality of workers these days, but I still maintain that lowering the standards and expectations is not an acceptable approach to correcting the situation.

For mine own part, I'm just glad I'm no longer in the homebuilding business. :)

06-22-2019, 12:50 PM
I think only a small % of consumers are half as educated about tile as the OP. So these tile guys never get called on mistakes. Most homeowners don't care.
Two very recent examples are my brother just built a big house in Denver didn't even want to talk about how they were doing the 3 showers. I have no idea except I know they are very expensive just the glass enclosures are close to $5,000 each I would guess. The kitchen backsplash tiles are hard and fast against the granite.
A man at the poker club didn't even want to talk about water how how he was going to waterproof his durock wallboard in his shower or the shower base or drain.

I dont think that many installers have used linear drains, ditra heat, much less heat in the shower. I'm not sure how the installer didn't know to use kerdi band in the corners but maybe he was told what to do and and supplied materials, obviously had lots of Kerdi fix on the job. To these guys there is no time to go buy some kerdi band or other thing if they forgot something. They just make do because time is money.

06-23-2019, 07:30 AM
"To these guys there is no time to go buy some kerdi band or other thing if they forgot something. They just make do because time is money."

Yes, you nailed it. The tile guys were missing some materials and instead of waiting for the GC to get them, they plowed ahead with the installation so they could get to the next job. There are mistakes on all sides, and I choose the GC so that's on me as well. I am fortunate to have the information and resources available online and your forum to work with them on addressing the issues. If it's not done by the (Schluter) book, but works equally as well, that is an efficient solution for me at this point.

Teddy, the plywood subfloor itself was sloped towards the entrance of the shower and drain. Tilers laid down Schluter all-set, then the ditra mat and the ditra heat cables, then more all-set and tiled over it. There was no Kerdi waterproofing on top of the heat cables in the shower. Those guys refused to re-do it and left. New tiler popped off the old shower tiles, removed as much all-set as possible and tested the ditra cables. Then he put down Mapei Ultraflor Modified Thinset over the ditra heat, followed by Kerdi.

Schluter said--no, using another company's modified thinset would never be advised and voids the warranty, although they could not confirm that it would fail. If anyone has experience with these products failing together, please let me know. This week, new tiler will use Schluter all-set to tile on top of the kerdi. The Mapei will remain between the dirta-heat and Kerdi waterproofing, unless I tell them to re-do.

Because of that extra thinset, the shower floor is higher than it was before, but slopes towards the drain. And it may not be exactly flush to the drain, more like a waterfall. They also said the linear drain was framed and blocked off underneath. The shower drain is directly above a drywalled kitchen ceiling, so if there's even one drop of water everyone will know.

I realize this is not the norm, but I am open to making things work if they actually work. Our house was built in 1925 and this shower was a former closet. Very few good GCs willing to take on this job when they can have their choice of new builds right now.

06-23-2019, 08:14 AM
Does the thinset still feel squishy under the kerdi in the floor? It's probably not thick enough to tell. I just wonder if you get away from the edges if the thinset is still wet and tge kerdi will pull up easily. But maybe it will be ok as is. I'm no expert for sure. I just know if I make a big pile of excess modified thinset the next day there's a thin 1/8 inch crust and it's still soft inside. But it's not like there's any forces pulling your flooring up.

How thick is that plywood subfloor is it two layers?
How did they install that sloped plywood flooring on top of the other flooring? I'm sorry but I just do not get a warm fuzzy feeling about your drain subfloor installation.
Big leaks will maybe show up but it's small ones that don't show up but still cause damage down the road.
You will just have to make a judgment call on what you're comfortable with but I'm pretty sure no one here will say it's done properly.
I am imagining therecare two reasons why Schluter would want Kerdi on top of the ditra heat membrane in a shower 1 is to try to keep that cable dry even though it has insulation. #2 is that the larger thinset cross sections in the ditra heat allows more water seepage which is logical.

I wonder how intact the kerdie membrane has remained theough the tike removal?
You may want to get a mega ohmmeter that checks using a thousand volts to make sure your heating cable has not been compromised. A simple ohmmeter test doesn't really check for pin holes in the insulation that may trip your GFI circuit breaker that the heating system requires.
I'm wondering if they did not have Kerdi band how did they waterproof the wall Kerdi to the ditra heat flooring? Maybe they used Kerdi fix which is not a good method down there.

06-23-2019, 08:59 AM
Not sure why sometimes it qoutes myself?

06-23-2019, 09:07 AM
Then he put down Mapei Ultraflor Modified Thinset over the ditra heat, followed by Kerdi. I've not used the MAPEI Ultraflor, Kate, but from the manufacturer's description I think it a poor choice for that application. It's advertised as a "medium bed" mortar for use at thicknesses of between 3/8ths and 3/4 inch thickness, not what a fella would really want to use to bond his Kerdi membrane, modified or not. That and the caution under "Limitations" saying "Do not use for installations subject to prolonged water immersion."

Schluter would balk at its use simply because it's polymer modified, but I doubt they've ever actually tested it. We've found lots of modified mortars that will cure perfectly well under Kerdi, but that's not one I've tested in that application. And the manufacturer's caution not to use it in prolonged water immersion would make me not want to use it in a shower floor application.

And I doubt Schluter or any other manufacturer of similar products, would be happy with any of their products being applied over a plywood substrate in a wet area.

Will it all work out OK? I dunno. And if any of it is a serious problem you probably won't know for a few years, either. Might all be fine. Might not.

My opinion; worth price charged.

06-23-2019, 09:33 AM
It's been a long time since I've seen a GC that actually cares or knows what's going on. GC's trust their subs to run the job most of the time, which is a disaster waiting to happen.

06-23-2019, 10:12 AM
Correction: Mapei Ultraflor Plus Modified Mortar

The shower floor does not feel squishy, but it was put down Thursday and I can peel up the corner of kerdi like its strong duct tape. I don't like that, particularly to both your points about the bonding. I will reconsider allowing that to stay.

"And I doubt Schluter or any other manufacturer of similar products, would be happy with any of their products being applied over a plywood substrate in a wet area."

Would you please clarify for me, is plywood not a good substrate for a shower floor even with Schluter waterproofing? Also, I was wrong, it looks like there's plywood, kerdi on the floor and kerdi connecting the walls to the floor, then the ditra, then more kerdi. The kerdi-band was not used in the corners above the floor or at the seams of the kerdi-board but that is being re-done now.

A double layer of plywood was used. They shimmed and sistered the joists to raise, level, and slope the floor.

They used a multi-meter to test the heat cables. I will have them tested with a megohmmeter. Thank you for pointing that out, as I did not even think to check their equipment.

06-23-2019, 10:44 AM
Maybe I've missed that but I want to raise one point:
You have a Kerdi line linear drain, right?
If so, how was it bonded to the ditra before they pulled up the floor tile? And when they redid the floor with the extra layer of Kerdi between the heating cable and the new shower floor, how was the linear drain tied in then? I am asking because the flap of Kerdi fabric that is attached to the drain body itself cannot be pulled off and re-embedded without harming the fleece. Also, if they just ran the new Kerdi membrane over the old thinset on top of the drain bonding flap, you'll have too thick a layer of thinset there that is prone to wicking.

It's imperative that the handling of the drain is done correctly and carefully. That's the most vulnerable spot that will see the most water. The Kerdi drains cannot be torn up and redone as usually the bonding fleece is damaged in the process. They would have to be replaced for a redo.

I've only ever installed two Kerdi drains (one round, one linear) but I took painstaking care to properly tie them in with the rest of the membrane. It would have been unthinkable for me to tear them up in case of a mistake and just redo them for fear of a leak. You just simply cannot flub that part of the installation. It needs to be spot-on.

06-23-2019, 10:52 AM
Wolfgang, before the kerdi-line drain was installed, it looked like the kerdi collar had been taken off. The Kerdi from the shower was attached to the place the kerdi-collar should be. I am assuming with thin-set. The kerdi-fix would be better to use instead of thinset in that situation probably?

06-23-2019, 10:56 AM
Im making the call to urge you to pull the floor up now. if it pulls up like duct tape at the edges the center is going to come up like wet wallpaper.
Mapei › public › productsPDF
Web results
Ultra or Plus Ultra or Plus - Mapei

When mixed with water:
• Concrete (cured at least 28 days)
• Cement mortar beds and leveling coats
• Cement backer units (CBUs) – see the manufacturer’s
installation guidelines
When mixed with Keraply:
• Installations over properly prepared and well-bonded
ceramic and porcelain tile, quarry tile and pavers (interior
and dry conditions only)
• APA Group 1 and CANPLY 0121 exterior-grade plywood
(interior, residential and light commercial floors and
countertops in dry conditions only)

Dry conditions only even if mixed with 100% keraply

06-23-2019, 10:58 AM
I know it should have a collar, I asked about that when I saw it in there. It's difficult to explain to a GC who does not know what he is doing that something "looks wrong" without being able to give a solution. So I read in the Schluter installation somewhere that if there was no collar, kerdi-membrane could be attached with kerdi-fix to the linear drain, and I dropped it.

I will bring the drain collar issue and the mapei mortar issue to his attention immediately.

06-23-2019, 11:09 AM
The factory applied kerdi hopefully is very waterproof and then this should go on top subfloor or ditra heat then kerdie overlap 2". The overlap order isn't specified. Did they cut it off? How did they connect the drain going to the low wall by the door? I still say rip up that Kerdi and wash off as much thinset as you can. And send some pictures so we can decide what to do. This is what a drain looks like. If they didn't have ditra on top of the ditra heat when they took off your tile how was it supposed to be waterproof to the drain?
This isn't rocket science but it's close.

06-23-2019, 11:33 AM
Thank you, Teddy. Not nearly as pretty as a collar...

06-23-2019, 11:39 AM
I'm thinking your best to pull the drain out and just redo this whole floor. I can't begin to understand all those layers of Kerdi and thick thinset with voids . I can't imagine there is a good waterproof Bond from the Kerdi drain to the ditra heat or ditra. Your original kerdi drain
cloth may be down in there somewhere. . It does not look like these guys know how to install ditra and they did not use a Kerdi sized trowel.

06-23-2019, 12:18 PM
Some thinset mortar will cure and attain full strength if it can't dry out, some does not. Check with Mapei about the one used. If it cures to full strength while wet, it should not be a problem. The issue is, the Ditra Heat and Kerdi are both waterproof. There's essentially no reliable way for thinset to dry out in between. If it is one that needs to dry to attain strength, it could fail. If it isn't, it should be okay. It might take years, but eventually, it will dry.

06-23-2019, 12:28 PM
Kate, if by "collar" you mean the Kerdi fabric attached to the drain, then no, that should NEVER be taken off. It is attached to the steel drain body with a red factory-tested sealant. It ensures the integrity of the drain's waterproofness. You need the overlap from that flap to tie it into your surrounding Kerdi installation. Re-doing the bond between the drain body and Kerdi with Kerdi-Fix is sketchy at best. I wouldn't rely on that at all. There's a reason why that process is done at the factory with a sealant that, at least judging from its color, is different from the Kerdi-Fix.

From what I can discern from your pictures, there seem to be voids between the Kerdi layers. That doesn't look like a neat installation done according to best practices.

06-23-2019, 12:32 PM
I was leaning towards hope in that direction Jim. But reading the thinset is not for wet locations. Used for Floors and countertops. Thend seeing the thickness and voids of that thinset and the overall schluter knowledge of the workers i say it's time to call it. I'm the tightest guy in most rooms. I know the drain body is 450$ on Amazon and a new hearing cable but I say it's time to bite the bullet for 1000$+ which is probably 10-20% of this showers price and do this shower right. It sounds like we can save the walls and redo this floor and drain and tie the Kerdi into the walls and end up with a good solid chance of a waterproof shower that will last for 30 years.

06-23-2019, 04:34 PM
Thank you for your consideration. I agree the drain must be replaced and the part of the shower floor where the mapei was used. I will have the heat cables tested with a megohmeter and hope for the best.

07-13-2019, 08:33 PM
Custom tiled shower with a Schluter cove profile on the shower floor. I don't understand why all the cuts are jagged and uneven. Is there any way this install meets industry standards?

07-13-2019, 09:26 PM
Kate, I don't mean to be cynical but those are some super ugly cuts for sure. Looks like they marred the Schluter trim in the process, too, or is that just a reflection? Is that the soft PVC Dilex or a metal trim? A traditional silicone-filled joined suffices and would have probably looked better.

Also, the marble you picked is already showing signs of oxidization from the iron contained therein. If I had to guess there will probably be more of it in the future. Some people say mostly the budget marble is prone to that but I don't know enough whether that's true or not.

Have any of the previous issues been addressed?

Disclaimer: I am an amateur but have worked with a range of Schluter products for two shower remodels.

07-13-2019, 09:59 PM
Thanks Wolfgang, yes, everything was addressed and fixed with guidance from this forum and schluter. Then this tile job happened.

The tile itself is actually a beautiful calacatta from Italy, so there is some gold veining and I’m ok with the living finish of it. It doesn’t look great in this pic bc of grout haze and also the tile installer didn’t use a vacuum (like at any point) so it’s super dirty. I don’t want to trash anyone’s work, but I’ve only ever looked this closely at my own house. My expectations may be skewed from website/social media photos ?

07-13-2019, 10:55 PM
Kate, you're not being picky. Those cuts aren't in any way acceptable. There's really no reason for someone to install those cuts as they are.

07-13-2019, 10:57 PM
And I agree with Wolfgang that those profiles don't appear to be the ones designed for that application.

07-13-2019, 11:08 PM
In fact, are yours the cove metal profiles described here:

If so, this is primarily for countertop to backsplash transition. Read the part about limited movement carefully. Your shower wall to floor joint needs movement accommodation. Schluter makes such profiles as well but they're different, not metal. Most simply, a 1/8 in silicone joint would have been all that was required for movement accommodation.

07-14-2019, 05:45 AM
Actually they are the dilex PHK, which would be okay in this situation except he floated out the grout line almost 1/2" instead of flush to the spacer for a 1/8" joint line. Which looks just about as sloppy as the cuts, so there's that too.®-DILEX-PHK/p/DILEX_PHK

07-14-2019, 08:05 AM
Again, Kate, you'll notice the clause about "where limited movement is expected" in your link.

What they should have used had they paid heed to details:

The manufacturer does the research and development. I think we're well advised to follow their guidelines. Not your fault, obviously, but your professional should know this stuff. Problem is, he doesn't read enough. It's all there laid out.

If it were me, I would have opted for the Dilex HKS made from actual stainless steel. Longterm durability and beauty over PVC. Would look sharp with an Italian marble such as yours (or any other tile, in my very personal opinion).

07-14-2019, 12:05 PM
Kate, just like anything else that's hand crafted, the installer's eye to detail is important for a nice looking job. It's not an accident when a job comes out looking good. It means the installer took the needed time to make it that way. Most likely the installer thinks his job looks just fine.

Edit; Another thing or two. There are times when the installer can get by with using a grinder to make his cuts. So many get lazy and want to make all their cuts with a grinder which might be what this guy did and you can see the outcome. Also, you can see by the difference size of the cuts, the floor is way out of square. This floor would have been squared up long before most installers ever started tiling anything.

07-14-2019, 07:58 PM
I really can't tell what profile he used. There's so much grout or thinset left on I can't even see what kind of corner joint he used. It looks like he left something on the finish that messed up the Finish coat each stick of Schluter trim comes with a warning to wash thinset off quickly. Very sad to see poor craftmanship. Not just a bad cut here and there but so many in such a small view.