# LOOK at this DITRA



## angus242 (Oct 20, 2007)

Bastien1337 said:


> would using modified thinset under the ditra over the cbu not have a stronger bond much like using it on tile over the cbu?
> 
> or is it a case of its not necessary?


Modified thinset between Ditra and anything cement-based can take days to cure. That's why Schluter wants non modified in that situation. Some guys use Versabond instead. It's a lightly modified thinset. 

However, what you're alluding to is that somehow, CBU benefits the situation. It doesn't. Use one or the other, not both. Unless you need to raise the tile floor height greatly, leave the CBU at home when using Ditra.


----------



## Bastien1337 (Dec 20, 2010)

angus242 said:


> Modified thinset between Ditra and anything cement-based can take days to cure. That's why Schluter wants non modified in that situation. Some guys use Versabond instead. It's a lightly modified thinset.


I appreciate the input and I do believe I get where you're coming from, but out of curiosity (im sure i will go back and re read the ditra book i bought from the JBforoums) How is using a modified thinset over a porous sub-strait like plywood different then using a modified thinset over a porous sub-strait like concrete? if they are both underneath the ditra?

I understand the argument of using a non modified over concrete underneath the ditra because it is a cement to cement connection but concrete is still a porous material its not like the tile between the kerdi?

am i just flat out wrong on this?


----------



## opiethetileman (Apr 7, 2005)

i got some shirts and hats and a few other goodies..............also some new floats.......I had a float fall apart and called and they fixed it right away after I showed a photo on the 7 floats I have and some are very old and still work


----------



## angus242 (Oct 20, 2007)

Bastien1337 said:


> I appreciate the input and I do believe I get where you're coming from, but out of curiosity (im sure i will go back and re read the ditra book i bought from the JBforoums) How is using a modified thinset over a porous sub-strait like plywood different then using a modified thinset over a porous sub-strait like concrete? if they are both underneath the ditra?
> 
> am i just flat out wrong on this?


Yes, that is incorrect. From Herr Schluter:
_"Unmodified thin-set mortar is not moisture-sensitive, not alkaline-sensitive (the mortar itself is alkaline because it is a cementitious product), and won't support mold growth because it is alkaline (mold requires a neutral to acidic environment). We have never had any issues with DITRA over concrete that could be attributed to moisture vapor emissions."_

I assume part of their specs have to do with moisture issues and concrete. There are lots of folks that skirt the Schluter rules and use a slightly modified thinset over concrete. It's up to you.

But with a properly prepped slab, using Kerabond is more than sufficient.


----------



## Tech Dawg (Dec 13, 2010)

If you need to build the floor up can you glue/screw or thinset down some ply


----------



## angus242 (Oct 20, 2007)

If you're adding more ply, simply screw it down. Use flooring screws and make sure _not _to penetrate into the joists.


----------



## Tech Dawg (Dec 13, 2010)

So, ditra on ply u have to use modified... but concrete, cement board u use un_modified and the tiles always lay in un_modified


----------



## angus242 (Oct 20, 2007)

Enola Eagle said:


> So, ditra on ply u have to use modified... but concrete, cement board u use un_modified and the tiles always lay in un_modified



Bingo!! :thumbsup:


----------



## Tech Dawg (Dec 13, 2010)

I saw in their handbook that if you go over vinyl to use rapid set,but I think that I would feel better tearing it out... u?


----------



## angus242 (Oct 20, 2007)

Yes, I always like to tear out everything back to original subfloor. That way, I'm not relying on someone else's install.


----------



## Tech Dawg (Dec 13, 2010)

Onto thinset... here's what's readily available in my area... 
Lowes- LAT. Floor adhesive, multipurpose, gold
Depot- versabond, custom blend(non)

I have to order 317 from my normal supplier(ProSource) at a higher $ and noone here has heard of kerabond.

DalTile has the same as depot but I don't shop there cuz if your not a 150k per year account they treat u like s#*t


----------



## Tech Dawg (Dec 13, 2010)

I ask because I'm switching to ditra, because my back told me to  and I'm looking for the 2 and only thinsets to use that are the best quality


----------



## angus242 (Oct 20, 2007)

Dal carries Mapei & Laticrete. I get Kerabond for under $10/bag.

These are the only unmodifieds I'd use:

Mapei Kerabond
Mapei Keraflor
Laticrete 272
Laticrete 317
DitraSet


----------



## angus242 (Oct 20, 2007)

If none of those are feasible, I suppose you could break the law and go with Versabond.


----------



## The Coastal Craftsman (Jun 29, 2009)

angus242 said:


> If none of those are feasible, I suppose you could break the law and go with Versabond.


Is that the crap HD sells? If it is I used that once and never again.


----------



## opiethetileman (Apr 7, 2005)

wow glad I took theese pictures it seems alot of questions with them


----------



## angus242 (Oct 20, 2007)

Yes and LOTS of guys use it with Ditra.


----------



## Tech Dawg (Dec 13, 2010)

I'll probly stick to 317 and use the latex additive when I need it or check with the mean guys at dal on kerabond...

317 is about 16 bucks which is fine, 272 was just raised to $22 since it is discontinued and 317 is the substitute, makes sense huh...


----------



## angus242 (Oct 20, 2007)

Enola Eagle said:


> 317 is about 16 bucks which is fine, 272 was just raised to *$22 *since it is discontinued and 317 is the substitute, makes sense huh...


 You in Canada?


----------



## Tech Dawg (Dec 13, 2010)

Ditra or Ditra xl? Do u hang your hat on one or the other or combo?


----------



## HS345 (Jan 20, 2008)

angus242 said:


> You use Ditra _instead _of CBU, not with it. And as stated, it doesn't float.
> 
> There are a few materials which will accomplish this. However, like was already said, the theory is to not allow substrate movement to the finished floor. There are other benefits, such as you waterproofing.
> 
> Some buy into the uncoupling principle, others don't. I do. And what I can sell to my customers is that little bit extra insurance that my installs will last.


I don't think he meant over the top of cbu, I think he meant instead of cbu. IE, choosing Ditra over cbu.


----------



## angus242 (Oct 20, 2007)

HS345 said:


> IE, choosing Ditra over cbu.


:blush:


----------



## TileWizard (Jan 14, 2011)

katoman said:


> The simple explanation is if there is any movement in the structure, it is not transmitted to the tile.


 i understand that, makes perfect sense. something about it just seems not as sturdy. and seems like my grout lines would crack

id like to make the switch. i have a 450' floor this week so i think im gonna give it another whirl


----------



## TileWizard (Jan 14, 2011)

HS345 said:


> I don't think he meant over the top of cbu, I think he meant instead of cbu. IE, choosing Ditra over cbu.


this


----------



## Tech Dawg (Dec 13, 2010)

I know one thing... Ditra is a heck of a lot easier on the back and knees! 
No? As we speak I'm applying for my friggin marriage liscence with the stuff...


----------



## katoman (Apr 26, 2009)

A brief, albiet incomplete history -

The egyptians, romans, etc. laid ceramics on a sand base. (may have had some other ingrediants in it)

Then we got to installing with a mortar base. Thick, 2-2 1/2". Same effect, ceramics free of the structure.

Then someone started laying with wire mesh, cement got thinner and thinner. Not the same thing now.

Then someone invented cement board. OH it's faster! Now it's attatched to the structure. Completely wrong.

Now ditra (not sure if there are others, probably) Ditra accomplishes the same thing as the sand or cement sand substrate. It allows seperation from the structure.

The use of screwed down sheet goods was the deviation from standard practice. Not the accepted method. Never was.


----------



## TileWizard (Jan 14, 2011)

interesting


----------



## Tech Dawg (Dec 13, 2010)

Another small claim is that unmodified thinset is weak? Tile will bond to vitually any thinset and back in the 50's etc... you couldn't buy admix. Wet bed tile installs are solid and a b$*ch to tear out... I would honestly go to that method before using cbu again but for now I'll stick with kerdi& ditra


----------



## angus242 (Oct 20, 2007)

TileWizard said:


> interesting



Pretty easy to get hooked onto the concept, eh?

Wait until the first time you install a membrane. You will definitely be hooked. 300+ sq ft of underlayment weighing less than 100 lbs. Cutting with only a blade. Can fit 1000 sq ft of membrane in the rear of an extended pick cab.

:clap:


----------



## Tech Dawg (Dec 13, 2010)

Angus would be a great crack dealer...


----------



## angus242 (Oct 20, 2007)

If crack was as easy to sell as a membrane, I might consider it :laughing:

Honestly, the less my competitors sell them, the better for me.


----------



## Bastien1337 (Dec 20, 2010)

angus, when you use ditra do you still beef up the subfloor?


----------



## HS345 (Jan 20, 2008)

Tech Dawg said:


> Another small claim is that unmodified thinset is weak? Tile will bond to vitually any thinset and back in the 50's etc... you couldn't buy admix. Wet bed tile installs are solid and a b$*ch to tear out... I would honestly go to that method before using cbu again but for now I'll stick with kerdi& ditra


Of course, back in the fifties they didn't have porcelain tile either. But if anyone doubts porcelain can be bonded with unmodified, back butter two pieces of porcelain tile, notch one and stick 'em together. Let them cure for at least 24 hours, and try to pry them apart. This should put to rest any doubt you may have about the ability of unmod to bond porcelain tile. But, in order for unmod to bond to porcelain, it must be sandwiched between two impervious layers. This allows for wet curing, and increased strength. Hence the two pieces of porcelain for our experiment.

I still prefer the Ardex FB-9L though. :biggrin:


----------



## JohnFRWhipple (Oct 20, 2009)

Tech Dawg said:


> Another small claim is that unmodified thinset is weak? Tile will bond to vitually any thinset and back in the 50's etc... you couldn't buy admix. Wet bed tile installs are solid and a b$*ch to tear out... I would honestly go to that method before using cbu again but for now I'll stick with kerdi& ditra


Non Modified thin set is much much weaker than modified thin sets. This is a simple fact and yes you are correct that the old jobs where a bear to remove because they where wet set on to a mortar bed most times 1 to 2 inches thick and with chicken wire set as reinforcement like rebar. These old jobs also had an uncoupling membrane - it was called " building paper ". 

The building paper creates a bond breaker so the mortar bed can float over the sub floor. 

Now we have crappy thin set that is non modified and out of date sold all over the country - yours and mine. Mastic stocked in ratios most likely 2-1 over modified and more like 10-1 over non modified.

Back in the day this mortar was made on site and if you want to save some money you can set with a nice. 4-1 mix. Just build it like they did then.

If you want to go flat. Use better setting materials. If you are going to heat the floor or if the floor receives direct sunlight consider modified thin sets but then realize there is much to learn about drying times. Study up on Mortar fatigue...

There is a science in this business an lots to learn. The more I learn about Schluter and its policies the more their competition looks better to me.

It is a good product. Don't get me wrong. There just is much better ways to do it. Their training manuals leave much to be desired and watering down non modified thin set is a sure recipe for failure long term. 

A side note... Nobel TS out performs Ditra as an uncoupling membrane....

Just saying...


----------



## JohnFRWhipple (Oct 20, 2009)

katoman said:


> ... Now ditra (not sure if there are others, probably) Ditra accomplishes the same thing as the sand or cement sand substrate. It allows seperation from the structure...


Good point.

Like I mentioned above. So does Building Paper. Like they did back in the day.


Here is a thread here on Contractor Talk with a whole list of other options. I believe all of them allow for modified thinsets...

"Other options in uncoupling membranes"


JW


http://www.contractortalk.com/f73/options-uncoupling-membranes-what-different-options-88002/index2/


----------



## JohnFRWhipple (Oct 20, 2009)

*A better test*



HS345 said:


> ...But if anyone doubts porcelain can be bonded with unmodified, back butter two pieces of porcelain tile, notch one and stick 'em together. Let them cure for at least 24 hours, and try to pry them apart. This should put to rest any doubt you may have about the ability of unmod to bond porcelain tile. But, in order for unmod to bond to porcelain, it must be sandwiched between two impervious layers. This allows for wet curing, and increased strength. Hence the two pieces of porcelain for our experiment...


How about this test.

How about you take 2 porcelain tiles and set them back to back like mentioned above but set one tile with a 1/2 span overhang. Use premium non modified thin-set for one.

Do another test using premium modified thin-set with the same 1/2 span overhang.


Give both tiles one or two days to set up and then clamp them to a shop table. Start stacking bricks on both test subjects.

My money is on the modified thin-set.

Any takers?

How about I run the test and anyone who wishes to prove me wrong do a similar test and lets pool the data...

Since I'm setting tomorrow in my kitchen and have all the stock on hand this mock up should take me maybe a half hour to rig up.

I do love proving things with fact. I'm tired of the half truths told to me by "Salesmen" and wish I could share 1/4 of the stories emailed and told to me in person...

Lets see what's stronger.


----------



## HS345 (Jan 20, 2008)

JohnFRWhipple said:


> How about this test.
> 
> How about you take 2 porcelain tiles and set them back to back like mentioned above but set one tile with a 1/2 span overhang. Use premium non modified thin-set for one.
> 
> ...


That sounds like a good experiment John. I'll do it when I get time. How about you do it too, and we'll compare notes. 

Good point about over watering thinset, it can be detrimental, you have to be very careful. That's why I like the Ardex FB-9L, it is designed to be pourable. It is designed to be fluid, but it will still hold a combed ridge, strange technology. This stuff is highly modified, and groutable in six hours. It is self hydrating. 

You know, Schluter's prohibition of modified mortars is only for North America, in Europe they have no problem with the use of self hydrating modified mortars whatsoever. They allude to that even in their literature here by condoning the use of "rapid sets".

I agree, Schluter has some strange business practices, but I don't think they are a bad company, just overly cautious.


----------



## Cletus (Jan 7, 2008)

I like stuff like this. Posts the results of your tests!

Keep adding weight until both samples fail and estimate the totals. Maybe allow for some 14 or 28 day curing times, not just the minimum time until grouting is allowed, since you're interested in the final adhesion.

I predict broken tiles before either type of completely cured thinset fails.


----------



## ApgarNJ (Apr 16, 2006)

whipple, you use modified to put kerdi over drywall or other wallboards? that is now how it says to do it. I just used kerdi for the first time several months ago at a beach house bathroom remodel. I use un-modified to put the kerdi over the greenboard, and butted the seams, kerdi band over the seams.

the only time you should use modified is with Ditra over plywood. what about KERDI over plywood. This is getting confusing. I have to see where I can take the schluter training because I think I know until I read threads like this and one guy says this, and another guy says this and it's too freakin confusing, no wonder why people have failures with this stuff. 

I've been doing tile over hardie (last 7 or 8 years) and durrock before that, and never have had a callback. I honestly don't buy that, water is going to get through the grout SO much during a shower that is it's going to rot out hardie backer board and cause failure. 
I have ripped out bathrooms from the 70s that put tile over normal drywall, with mastic and the only failure was at the very bottom where the tile met the tub and that is usually a caulk issue that cause wicking of water up the drywall. the rest is usually FINE and the drywall is good. 

I'm not saying to do it this way, but i often wonder is kerdi that much BETTER or a shower, or is just easier to install because you can roll it on over drywall. What sucks is that you have to really wait until the next day to install the tile. With hardie, you can tape the seams and start tiling right away with no worries of the membrane pulling away.

I'd love to go back and rip out a job done with 1/2 hardie over studs and see if there is any signs of water penetrating and ruining the hardie or causing issues.


----------



## Tech Dawg (Dec 13, 2010)

My personal opinion is that Schluter should be manufacturing and stamping their name on thinset, grout etc.... and offer the full friggin package. But what large coorporation is willing to do that? No? Its not like other thinset companies would go under cuz they can lobby with big box stores for the economy line.... Oh, and Home Depot in Mechanicsburg, PA is now selling Ditra... what is up with that? Is schluter going to make economy versions for Depot....
I hate finding a good product that is supposed to be for professionals and then 2 days later see it at depot and on top of that... depot has become even more of the devil by having appt. setters running around the store trying to steal biz from other contractors, smh


----------



## ApgarNJ (Apr 16, 2006)

my HD sells DITRA only, not XL, not KERDI, but they have a display rack of profiles though in alum for different applications. i rarely ever buy thinset from HD. I just don't have a good supplier in my area that STOCKS the right thing. TEC un-modified worked just GREAT for me doing the kerdi.
I think any quality thinset that is un-modified for kerdi or ditra is going to be just fine. Some guys use what is at their supplier and they think that is the only way to go, and that's ok for them because they live near there and that's what's there. TEC is nothing from CHEAP thinset. I've used their large bags of modified before, or super flex, ultra flex and you are talking 40-50 bucks a bag.


----------



## Tech Dawg (Dec 13, 2010)

Same at my local depot... they got ditra but nothing to seal your seams with... makes sense huh! Bad for home owners... good for me.
I guess you gotta buy your time and wait to get all the "blotched homeowner" tile redos... :/


----------



## JohnFRWhipple (Oct 20, 2009)

*Selling Ditra / Kerdi and not stocking Non Modified Thin Set*



Tech Dawg said:


> Same at my local depot... they got ditra but nothing to seal your seams with... makes sense huh! Bad for home owners... good for me.
> I guess you gotta buy your time and wait to get all the "blotched homeowner" tile redos... :/


I pressured my local box store to stock Non Modified thin set. It took six months and then they did.

All of what I write here is based on my own personally expierences in the field and my own phone calls with Schluter head office, Schluter's top tech and my local rep. These points I make are so easy to prove. Just call Schluter.

Schluter in the US
Schluter Systems L.P.
194 Pleasant Ridge Road
Plattsburgh, NY 12901-5841

Tel.: 1-800-472-4588
Fax: 1-800-477-9783

Schluter in Canada
Schluter Systems (Canada) Inc.
21100 chemin Ste-Marie
Ste-Anne-de-Bellevue, QC H9X 3Y8

Tel.: 1-800-667-8746
Fax: 1-888-667-2410

Now if your a Pro, a GC, a member of a building association or a tile association you most likely have a local "Sales Rep". They might tell you things like - it's OK to use modified thin set here. For this job it's OK. But when your job fails (if it fails) do you think they have your back or theirs.

In my last Schluter training class the Schluter boys talked about a meeting they had with their corporate lawyer. I was told the meeting started like this "...It's not if we get sued. It's when we get sued..." 

Maybe you boys have been told things like this over the years...

"I can't say where but this building down on ABC Street has 400 showers that are going to mold out because they used modified thin set on the wall tile." 

"You can't use modified thin set with porcelain tile because it won't ever dry out - it starts to mold in the middle"

a few years later you seek more advice and on this job it's OK. Just don't "Quote Me"...

Doesn't give me a warm fuzzy feeling... And then what about the rumour of a commercial project in Vancouver or Toronto with 400 plus showers, all kerdi, all getting ripped out because they are leaking... Is it a rumour? Maybe? Maybe not? Lets wait and see if any pictures pop up? Lets wait a see if Schluter replaces them? Lets wait and see if a tile contractor looses his shirt over this? Lets wait and see who tests the thin set? 

If it's true I hope they used non-modifed thin set. If it's true I hope they didn't use a little extra "red guard" on the seems. From what I hear that's a deal breaker and you deviated from the installation specs.

I also heard an inspector failed a kerdi shower with extra Red Guard on the Island. The inspector is right in failing this project - if the building (Damp Proofing) inspectors do their job 100% by the book it clearly states that these waterproofing materials have to installed as per their printed installation. So if your told it's OK to go with modified thin sets in the field.

"ASK FOR PRINTED INSTRUCTIONS FROM SCHLUTER AND COVER YOU BACKSIDE"

JW


----------



## ApgarNJ (Apr 16, 2006)

I understand what you are saying john, I might have misread what you wrote earlier but i thought you were pushing modified with kerdi for added vibration resistance with neighbors etc. or did you mean something else?

what do you install your kerdi over?

The more I read about this, the more I just want to go with hydroban.


----------



## Tech Dawg (Dec 13, 2010)

John, you always have a lot to say...lol
I was referring to kerdi band to set on your seams... I buy from prosource floorcoverings but I was just stating that it is idiotic on depots part to stock Ditra and make you do a "special order" for kerdi band


----------



## HS345 (Jan 20, 2008)

Tech Dawg said:


> John, you always have a lot to say...lol
> I was referring to kerdi band to set on your seams... I buy from prosource floorcoverings but I was just stating that it is idiotic on depots part to stock Ditra and make you do a "special order" for kerdi band


They don't sell Kerdi Band at HD, so you'd hafta "special order" that anyways. :whistling

Versabond works great for Ditra, Kerdi, AND Kerdiband. 

John, if Schluter is such a baaaaaad company, and their reps are giving all this baaaaaaad advice, where are all these failures that Schluter refuses to stand behind? Surely there would be something on the internet.


----------



## JohnFRWhipple (Oct 20, 2009)

*You can't use Modified Thin set with Kerdi - You can with Nobel TS*



ApgarNJ said:


> I understand what you are saying john, I might have misread what you wrote earlier but i thought you were pushing modified with kerdi for added vibration resistance with neighbors etc. or did you mean something else?
> 
> what do you install your kerdi over?
> 
> The more I read about this, the more I just want to go with hydroban.


Here is a link to the 2010 Schluter installation Handbook. Can anyone show me the page or any text where it allows for "Modified" thin set???

Why does a floating flooring installer not put the floor tight to the walls?

Why do you keep a space between subfloor sheets?

Why do you need expansion strips on large tile installations?

"Expansion" and "Contraction"

If something is "Cold" and then it gets "Hot" what happens? "Expansion" Where can this happen...

Over heated floors. South facing rooms. Shower floors... and on and on...

Now you take two showers both equal in every way. One you set with Kerdi by the book and the other with Nobel TS.

Nobel TS can handle more expansion than Kerdi in my opinion because it is designed too. Nobel 150 does not fully cure and remains flexible in the seams.
With all of my research and testing and field study I will always use Kerdi Fix in replacement of Non modified thinset in my seems. This is allowed by Schluter. It says so on the specs for Kerdi FIx.

I actually prefer Kerdi Fix over Nobel 150 and wish I could use my Kerdi Fix with my Nobel TS installs. Minor differences but I find the Kerdi Fix grabs faster and hardens a hair harder...

What type of expansion capabilities do you think Non Modified thin set has?

Ask a Laticrete rep? Ask a Custom rep? Ask a Mapei rep?

Has anyone every heard of a pool being built using Kerdi as a waterproofing material? Does Schluter recommend Kerdi if you call them? Can you use Kerdi in a exterior water feature?

Can you use Aqua Defense or Hydro Ban in these locations? You bet your A$$ you can. Call Schluter and ask them if you can use Kerdi to waterproof your pool and what type of thinset you can use to set your glass tiles over top...

Let me know what they say.

Then call Mapei and ask them.

Then call Custom and ask them.

Then call Laticrete and ask them.


----------



## ApgarNJ (Apr 16, 2006)

John, I wasn't saying to use modified! you made it seem like YOU do. you have so many questions. I don't know where to begin lol. I know what to use. 

so as long as you do, then you are ok. no need to get excited.


----------



## JohnFRWhipple (Oct 20, 2009)

ApgarNJ said:


> John, I wasn't saying to use modified! you made it seem like YOU do. you have so many questions. I don't know where to begin lol. I know what to use.
> 
> so as long as you do, then you are ok. no need to get excited.


I'm not excited. I just like to show another side to the coin. Travel the web and you will find all kinds of advice and lots of it is false.

And I like to use Rapid setting modified thin set for my Sheet membrane installations. I also like to vaccum them the following day to remove any dust and such.

Because of this I have had to find new suppliers for my projects. I was asked not to "Quote" my rep and keep my "Private Calls" and "Site Specific" information off the internet. This made me doubt the source.

What would you do?


----------



## ApgarNJ (Apr 16, 2006)

JohnFRWhipple said:


> Here in North America we have new rules because Schluter was sued over something a long time ago I believe.
> 
> I install my Kerdi with modified thinset - just not the seems. Kerdi fix there instead.
> 
> ...


Why would you SAY that you USE modified when they clearly state not to when putting kerdi on?


----------



## JohnFRWhipple (Oct 20, 2009)

ApgarNJ said:


> Why would you SAY that you USE modified when they clearly state not to when putting kerdi on?


Excellent Question!

I use modified because it's better. It's just not allowed if you are having inspections and want a warranty from Schluter.

Since I warranty my own work I want to use the best products. If you chat with the Pros many use modified thin sets. Many then add liquid membranes over their seems.

Years back I had an expired bag of thinset. I called my rep when my Kerdi lifted off when I shop vaccumed it and I was told I could get some replacement Kerdi (I never did get it because it was the thin set that failed not the membrane and it felt wrong taking new stock for my mistake). 

I learned a valuable lesson that day. Non Modified thin set is the cheapest product on the market. I also learned that if something fails I will get some new Kerdi and that is it!

So I went and learned how to do it better... To cover my bases and surprise surprise many top guys online endorse using "Modified Thin Sets"... Many use liquids over top... and since then I have not looked back. And I have always wondered why it is OK in Europe and not North America ??? :blink:

Now with further training and the introduction to Nobel 150 and Nobel TS I have found an even better approach. With liquid membranes coming a long way and 25 year replacement warranties - I have been switching things up...

JW


----------



## Bastien1337 (Dec 20, 2010)

the simple contradiction for type of thinset between the UK and north america is starting to give me an uneasy feeling.

this excerpt is straight from the UK Schluter website:
_
The type of bonding adhesive used to
apply Schlüter®-KERDI depends on the
type of substrate. The adhesive must
bond to the substrate and mechanically
anchor the fleece on the underside of
the Schlüter®-KERDI matting. Verify
the compatibility of all materials prior to
installation._

http://www.schluter.co.uk/produkt.aspx?doc=8-1-kerdi.xml&pg=download

I cant seem to find any place on the website itself that directs you to the type of thinset to use.


----------



## angus242 (Oct 20, 2007)

I'm not taking anyone's stance here. I will go out on the limb and say that Kerabond has never failed me before. The only time I've had an issue was when I didn't have proper coverage under Kerdi/Ditra. I'm the only one to blame for that.

Also, there have been times when I've had to pulled Kerdi back off for whatever reason. Even after as few as 15 hours, pulling Kerdi down would result in me actually damaging the Kerdi because of how well it was adhered.

I'm sure there are cheapie non modifieds out there. But it's up to the user to supply the proper materials, not Schluter. And Schluter actually has gotten into the thinset game....Ditraset anyone???? It's actually very good thinset. And yes, I know it's not made by Schluter but it is endorsed by them.

In Europe, Schluter does, in fact, offer a thinset to install their products....I don't know the details but it is a 2 part container (epoxy-like) and it is cementitious based! :shifty:


----------



## JohnFRWhipple (Oct 20, 2009)

angus242 said:


> ...In Europe, Schluter does, in fact, offer a thinset to install their products....I don't know the details but it is a 2 part container (epoxy-like) and it is cementitious based!...


Like a "Rapid Set" maybe?

Here in BC I'm told you can use setting materials that are modified as long as they don't need air to cure. I'm thinking those premium little 1 gallon Euro setting buckets are in fact a full epoxy with no cement.

Angus I know you set this stuff everyday and your clients are getting a killer install. I worry about Mom and Pop reading our posts and mixing these "Cheap" products with a 14.4 volt cordless, not damping down the surface, not working the mortar into the substrate, not back buttering and on and on.

Kerdi set with a premium modified rapid set with Kerdi Fix in the seams is going to make for a bullet proof install. Schluter sells the concept of speed. Set and tile in a day.

If your setting your tile in a day and you need to remove a tile and replace you are pulling on the membrane due to the suction it creates when installing 
it.

If your building a shower that you want to flood test (because that's code) do you really want to wait a few days until it's ready. I can set my Kerdi Showers with Kerdi and Kerdi Fix and flood them the following day.

Now don't even get me started about Efflorescence and the fact that non modified thin sets aid in all these "Whiting" effects in shower floors.... Many modified thin sets as well! Not Mapei's Grani Rapid. No No No...

I know as well that you use a premium grout - Urethane - Star Quartz, and not a cheap cement based grout...

But what about the family that bucks up for a nice black slate floor. Porcelain tile they use a good grout. Set with Non-Modified thinset over their Kerdi and then a month later the black or charcoal grout looks grey.... A top of the line shower install that looks like crap because they used the cheapest thinset on the market...

Efflorescence baby

It will destroy these installs if proper measure are not taken.

JW


----------



## ApgarNJ (Apr 16, 2006)

John if you use a quality un-modded thinset, and it's done right, you shouldn't be pulling off the kerdi. how much dirt is really getting over the kerdi from one day to the next that it needs to be shopvaced, does it say in the instructions that it needs to be shopvaced, maybe it pulled off because you used SUCTION on it when it's not meant for that. 

I trust schluter because they engineered this stuff, they say un modified is BEST to use for kerdi!, that's what i''m using.

Angus here has done a lot of kerdi and I trust him 100% to steer me in the right direction. WHY take the RISK of using modified when they say not to???
how do YOU know it's better?? the only reason the unmodified is cheaper is because you aren't paying for the ADDITIVE to be put in there ahead of time from the factory, I'd bet the mortar/thinset part is EXACTLY the same just with no additive. that's what you are paying for.

I don't think you should be on HERE confusing people who read this who may want to use it for the first time when the instructions say the opposite. 

I hope you never have a failure by using modified with kerdi over whatever wallboard you are using, drywall, etc.

if you want to do it the wrong way, keep it to yourself, don't spread it all over the internet. if schluter thought it was better to use modified, they would PUT it on the packaging!!!!!!


----------



## Tech Dawg (Dec 13, 2010)

We need Dr. Drew to sign up for CT, so he can help us work out these issues...


----------



## ApgarNJ (Apr 16, 2006)

JohnFRWhipple said:


> Like a "Rapid Set" maybe?
> 
> Here in BC I'm told you can use setting materials that are modified as long as they don't need air to cure. I'm thinking those premium little 1 gallon Euro setting buckets are in fact a full epoxy with no cement.
> 
> ...


john, you are knocking un-modified when you really need to just say DON't USE cheap ones. a quality unmodded thinset is not going to a problem.

if mom and pop are taking on a kerdi job themselves,t hen they deserve what they get. next time hire a contractor to do it.


----------



## HS345 (Jan 20, 2008)

Ditra has passed all relevant Robinson tests administered by the TCNA. What more do you want John?


----------



## Tech Dawg (Dec 13, 2010)

U guys are killin me... started a new thread...


----------



## TileWizard (Jan 14, 2011)

well my mind is blown


----------

