Iridescent Particles in Ardex's 8+9 Waterproofing - A closer look

[johnfrwhipple]

Another year has come and gone and I'm still not completed my review on this Ardex 8+9. I have to say that I love the product but am a little confused over how it preforms. We have used it once again on our latest job in tandem with Schluter System Kerdi DS.

I tried a little cold weather testing and found it the Ardex was left overnight in the cold it would not set when used to seam Kerdi DS. So like the liquid membranes temperature is a factor.

I have also found that the mixing is critical and that the proper Ardex 8+9 paddle needs to be used. The paddle works like a bread maker almost and really pushes the mix to the sides of the bucket while spinning.

I tried making a small batch with the paddle in a smaller container and found it quite hard to do. A full size mixing container is best.


After 90 minutes of flood testing you can see a slight change in colour.


After 27 hours the lighter colour is the third coat I used before flood testing. This coat was mixed in a smaller container.

Looking at this picture you can see two separate colours. One darker and one lighter (under water).

The shower has not leaked at hour 27 and was holding perfectly. This colour change I think the result of a less than ideal mix or mix time.

In the new year I'm going to continue this review of Ardex 8+9 and I'm going to compare it to Schluter System's Kerdi Col. I would also like to find a proper smaller mixer so I can mix smaller batches.

I was told that Robert Russell from Ardex would be out to Vancouver and would call on me. This never happen last month. Lets see if he makes the trip in January. I'm still waiting for a demonstration from my local Vancouver Ardex rep Glen and hope that this gets arranged this month. Until such time I'll continue testing this product and using it on my projects. I love the fact it's been around for 20 years and it's proving to be very versatile in the field.

JW

[johnfrwhipple]

I have also noticed something interesting about the Ardex 8+9. It seems to gas or create little pockets of air when curing. I have done a number of test boxes to first test that it holds water (never had one leak) and then how strong they are (the product is really strong - much more so than liquid membranes). In doing these tests and looking at cross sections of the dried product I see these little bubbles trapped inside the product.

I have never seen this anywhere outside of an Aero Chocalate bar.

Take a look at this swatch I tested in the cold.


This is Kerdi DS with a patch. I cut a hole to test how the product does in cold overnight lows (3 C).


Patch added over top with Ardex 8+9 only.


Left patch overnight in my truck and the next morning tried to pull it off. It came off with no effort and you can see all these tiny air bubbles. In the center you can see where the product dried (darker colour).


I pulled on the left edge and pulled the fleece right of the Kerdi. Nice bond strength there!

[johnfrwhipple]

Pockets of air in the Ardex 8+9


Once the patch was removed the Ardex 8+9 finished curing.

I'm curious as to the cure times here in heated environments. Because Kerdi, Kerdi DS and Kerdi Band are all waterproof the curing times must be much much longer. I have found that Ardex 8+9 cures to some degree even under water so measuring the time should not be that hard with the fact that the product goes from a light brown to a darker brown once cured. I'll need to use some plexi glass for this testing.

Knowing this one should use care when setting over a fresh band of Kerdi Band. If you pull the tile up to check coverage you might compromise your install.

So much to learn! JW

[johnfrwhipple]

At hour 27 I can see the first sign of the slight film layer I notice on the Ardex 8+9. At day two it starts to take shape and by hour 72 is quite pronounced. I was told that Ardex 8+9 is not designed to be left exposed and I get that. What I don't understand is why the product produces this.

If we know that it gasses to some degree (evident I think from all the bubbles) my hunch that a second reaction takes place once mixed is seaming more possible to me. Now I did not submerge the last test swatch so this gassing happens with out the incorporation of water.

I tested the powder in 8+9 with just water and found the same layer is created. I believe that it has to be the mix. making sure all the particles are incasulated with the liquid portion of 8+9. Watching my daughter make cookies the other day got me to thinking that perhaps my wife's mixmaster would be perfect for small batches of 8+9!!!

I wonder if this will fly?

"Hey Babe, can I take the mix master to work today?"

JW

[Daler]

Heya, John

Don't know if this is the proper thread to talk about this or not...

It's an interesting -- and timely-- review that you are doing. Too bad it's taken more than a year to complete it to your satisfaction

I am a layman homeowner who is just now putting in a 'custom' shower (36x58). My plan is to attempt a mud floor with a Kerdi drain, and cover it with Kerdi cloth (just enough material for the floor was given to me some time back) then up the sides about 8" with Kerdi-band. I'm not concerned with any warranty program so I'm thinking on using some Ardex X5 thinset under the Kerdi as well as for the field tiles -- that product was such a good choice for my other marble-tiled bath project. Have you used X5 under Kerdi?
The shower walls are just now Hardi'd. I then plan on using the Ardex 8+9 for the walls with overlap down onto the Kerdi clothed pan.

The Ardex package directions indicate that the Hardi seams and corners be filled and mesh-taped with the 8+9 -- no mention of pre-filling with thinset. But some of the gaps in the Hardi are large (about 1/4" at the niches for example). So what I propose to do is to first simply fill the Hardi with thinset and mesh-tape (as normal) then treat with the Ardex 8+9 as I did using the AquaDefense on my previous tub surround project. But my uncertainty here is with with the treatment of the corners as with the possibility of 2x4 stud movements. So, do you think the option of fully thinsetting the Hardi first would have any merit? As an aside, I've used Schluter eke for corner tile movement before and it seems to have worked as well as silicone.

Also, can the Kerdi be glued together successfully using the 8+9, or should I stick with the X5 or even Kerdi-fix? ..I'm not sure of your results as your review has yet to be finished.
And if so is there any advantage of just continuing the 8+9 over the whole Kerdi covered pan as a backup waterproofer? -- will it stick for the long term?

After resolving this, I also want to include building of a proper (low profile) curb. I figured I'd build it out of formed concrete. Is there a cationary method to use in doing this? I would also cover this with the Kerdi cloth ..and perhaps with a coat of 8+9 as well.

[johnfrwhipple]

Heya, John

Don't know if this is the proper thread to talk about this or not...

It's an interesting -- and timely-- review that you are doing. Too bad it's taken more than a year to complete it to your satisfaction

Sorry for the delay. I finally got an Ardex rep out to look at the slick that forms and I'm waiting on Don (Don Brcetic 778-870-5101) to do some training. This new Ardex rep was great and so helpful. He offered to come on our next job and review my procedures to see if my mixing technique is flawed. The Ardex 8+9 is the most promising new to me product I've come upon in a long time. I love it but think it is quite hard to mix properly. The proper paddle is a must and so is the size of bucket and the volume of each batch. If you use it do not do so until you test your product first. make a "Ardex Duck Box" and flood it out. If the liquid froze in transit you could have a failure looming.

I am a layman homeowner who is just now putting in a 'custom' shower (36x58). My plan is to attempt a mud floor with a Kerdi drain, and cover it with Kerdi cloth (just enough material for the floor was given to me some time back) then up the sides about 8" with Kerdi-band.

I'm not a fan of Kerdi on the floors - it's so thin. You can get Kerdi DS now which we just installed and it's a much better product for shower floors and steam rooms. Kerdi Band is for seams not walls. So if your plan is to run the Kerdi up the wall 8" use Kerdi and not Kerdi Band. Schluter also makes some great inside and outside corners.


I'm not concerned with any warranty program so I'm thinking on using some Ardex X5 thinset under the Kerdi as well as for the field tiles -- that product was such a good choice for my other marble-tiled bath project. Have you used X5 under Kerdi?

I have not but used loads of the X5 and love it as a basic thin set. Email Harrison from Ardex (Harrison Gardner Ardex Tec <Harrison.Gardner@ArdexAmericas.com>) he is there tech and he can let you know his thoughts on your plan.

The shower walls are just now Hardi'd. I then plan on using the Ardex 8+9 for the walls with overlap down onto the Kerdi clothed pan.

Backer boards are thirsty - all of them. And not ready for any waterproofing until they are taped and screwed off properly. Can you post a picture of your wall prep or email me so I can check how you did? What screws and what spacing etc... Of late we are making it a habit to scratch out the entire wall board during the taping procedure. This has greatly improved our working time and bond strength to the backer board. Anything over a 1/8" gap and my apprentice would be bitched out to no end. If you have 1/4" gaps in your backer board you are not off to a great start and should take measures of improving this.

The Ardex package directions indicate that the Hardi seams and corners be filled and mesh-taped with the 8+9 -- no mention of pre-filling with thinset. But some of the gaps in the Hardi are large (about 1/4" at the niches for example). So what I propose to do is to first simply fill the Hardi with thinset and mesh-tape (as normal) then treat with the Ardex 8+9 as I did using the AquaDefense on my previous tub surround project. But my uncertainty here is with with the treatment of the corners as with the possibility of 2x4 stud movements. So, do you think the option of fully thinsetting the Hardi first would have any merit? As an aside, I've used Schluter eke for corner tile movement before and it seems to have worked as well as silicone.

Do you have stucco mesh? Any Ardex X32? Ardex S14? Your waterproofing product should not be asked to seam gaps in your wall board. This is crazy to count on the waterproofing to add structure. Board. Tape with ideally a 4" mesh on the inside corners and a 6" tape on the outside corners. Small batches of rapid set, self curing thinset like the S14 work well. X5 and a few days cure time before waterproofing works to.

Also, can the Kerdi be glued together successfully using the 8+9, or should I stick with the X5 or even Kerdi-fix? ..I'm not sure of your results as your review has yet to be finished.
And if so is there any advantage of just continuing the 8+9 over the whole Kerdi covered pan as a backup waterproofer? -- will it stick for the long term?

I asked Dale Kempster (<DKempster@schluter.com>) what the equivelent of Kerdi Col is and was told it was Ardex 8+9. I have done a lot of testing and multiple products with Ardex 8+9 and Kerdi Corners, Kerdi DS and Noble Seal TS. All my testing has resulted in sucessful installs. All projects and test boxes where flood tested, my last for almost four days. Not a drop of water lost on any. The test boxes when finished we like to break apart. Some simple tests with liquids allowed us to use hand strength only to demo. The Ardex boxes require a good boot or two from the steel toes. Pretty impressive. Both my apprentice and I love the stuff. The X32 is pricey but so worth it. The 8+9 has been around for twenty years.

Go to the UK or German Schluter site and watch their installs. Ask yourself why they use Kerdi Col. Then email Schluter and ask if you can buy it here or what the North American equivalent is. Then email Ardex and ask about their ten year warranty with Kerdi - that's twice what Schluter will give you. Why do they double Schluter's warranty? Perhaps because it's twice the system. I alwyays hated the "Air of Bad Blood" I picked up on when my Mapei rep and Mapei tec's bitched about Schluter. Does not give me a warm fuzzy feeling when the setting material company I was using dislikes the Schluter product. Then I stumble upon Ardex and not only do they play nice - the warranty is double. This is a no brainer.

The first time I heard about Ardex was from another Schluter rep at Fontile. We where debating exterior decks and he mentioned the long history overseas with Ardex and Schluter. This rep mentioned something about better technology and I passed it off as a tiss at Mapei (I was wearing a Mapei fleecy at the time). Then I start seeing Ardex bags on so many job sites. Not low end reno sites but multi million dollar homes we wear on. HMMM. Then the kicker is the owner of Quick Drain and I where out for lunch and he tells me to try X32. I did and I love it. This coupled with my Mapei rep pissing me off was all it took to switch setting material companies. We are very happy we made the change and love all the products so far.

I have yet to test their grout and have been told they are still fine tuning this for North America. I have been told that Mapei's Ultra Colour Plus can be used in lue of Ardex's products but you better confirm this yourself. I do not have this on paper or by email as yet.

After resolving this, I also want to include building of a proper (low profile) curb. I figured I'd build it out of formed concrete. Is there a cationary method to use in doing this? I would also cover this with the Kerdi cloth ..and perhaps with a coat of 8+9 as well.

We like to use bricks. Rapid set thin set. This way the product is good to go the next day and not curing for 4 weeks.

Good Luck. Send me an email or call if you more questions. Give the guys above an email and confirm my posts.

I can not say how well the process of seaming the Kerdi with 8+9 will hold up long term and my hunch is that perhaps the safest bet is to install the Kerdi the way Ardex outlines and if you want added protection to then use the Ardex SK mesh and NOT Kerdi Band for the second seam. The SK Mesh rocks and has holes in it to allow the product to lay down flat with no air bubbles trapped underneath.


I strongly advise you to do a test box with the Ardex 8+9 and purchase the proper paddle to mix it with. A test box should be preformed with any waterproofing system.

Good Luck.

JW

[Daler]

..continuing the conversation..

[QUOTE=johnfrwhipple;366320]Heya, John

Don't know if this is the proper thread to talk about this or not...

It's an interesting -- and timely-- review that you are doing. Too bad it's taken more than a year to complete it to your satisfaction

Sorry for the delay. I finally got an Ardex rep out to look at the slick that forms and I'm waiting on Don (Don Brcetic 778-870-5101) to do some training. This new Ardex rep was great and so helpful. He offered to come on our next job and review my procedures to see if my mixing technique is flawed. The Ardex 8+9 is the most promising new to me product I've come upon in a long time. I love it but think it is quite hard to mix properly. The proper paddle is a must and so is the size of bucket and the volume of each batch. If you use it do not do so until you test your product first. make a "Ardex Duck Box" and flood it out. If the liquid froze in transit you could have a failure looming.

The paddles I've been using for my thinset are like these I purchased at Princess Auto -- one small, another larger
http://www.princessauto.com/pal/prod...n.-Paint-Mixer They seem to mix really well. Getting a genuine one from local supplier may be difficult here on the Island.

I am a layman homeowner who is just now putting in a 'custom' shower (36x58). My plan is to attempt a mud floor with a Kerdi drain, and cover it with Kerdi cloth (just enough material for the floor was given to me some time back) then up the sides about 8" with Kerdi-band.

I'm not a fan of Kerdi on the floors - it's so thin. You can get Kerdi DS now which we just installed and it's a much better product for shower floors and steam rooms. Kerdi Band is for seams not walls. So if your plan is to run the Kerdi up the wall 8" use Kerdi and not Kerdi Band. Schluter also makes some great inside and outside corners.

I was already given the standard Kerdi cloth for free and so I want to use it. Hence, my thoughts on going over it with 8+9 to be sure on thickness and durability. Yes, I can also use the standard cloth in place of the transition band going up the wall to meet the 8+9. There were some inside corners that came with the Schluter drain. Also, in John Bridge's book he illustrated a method of cutting his own corners


I'm not concerned with any warranty program so I'm thinking on using some Ardex X5 thinset under the Kerdi as well as for the field tiles -- that product was such a good choice for my other marble-tiled bath project. Have you used X5 under Kerdi?

I have not but used loads of the X5 and love it as a basic thin set. Email Harrison from Ardex (Harrison Gardner Ardex Tec <Harrison.Gardner@ArdexAmericas.com>) he is there tech and he can let you know his thoughts on your plan.

Just now doing a bit of research it seems that Ardex states that their thinsets are compatible with the Schluter Kerdi ..however, here in NA Schluter will not acknowledge the Ardex claim. I don't really care as the evidence points to numerous installers using modified thinset with Kerdi cloth, and Ardex being the best for that approach. I just wanted to see what your experience was with it as well.

The shower walls are just now Hardi'd. I then plan on using the Ardex 8+9 for the walls with overlap down onto the Kerdi clothed pan.

Backer boards are thirsty - all of them. And not ready for any waterproofing until they are taped and screwed off properly. Can you post a picture of your wall prep or email me so I can check how you did? What screws and what spacing etc... Of late we are making it a habit to scratch out the entire wall board during the taping procedure. This has greatly improved our working time and bond strength to the backer board. Anything over a 1/8" gap and my apprentice would be bitched out to no end. If you have 1/4" gaps in your backer board you are not off to a great start and should take measures of improving this.

Here are some pics of my project. Lotsa screws, eh




Note: the "wrinkled" look of the Hardi on the back "pony" wall where they join is actually some Hardi that was ground down to blend in with the bottom board. For some reason the latest batch of Hardi was a different thickness to the older stuff left from last project -- blech!

Having tried the authentic Hardi screws without much success (too hard to drive) I instead used 1 5/8" coated deck screws. They worked great on my last bath project ..but that's only been less than a year ago. I installed them 8" apart on average, 3/8" from the edges, and 2" back from the corners. However, some of the edges broke out when trying to hit the studs on an angle (should have put in more blocking I guess). You can see some of the damage in the pics. Also, the Hardi had to mate up to greenboard drywall in the rest of the room. Again, that's where most of the large gaps are. The 9x24" niches are on either side of the valve. The niches are covered with Hardi as well. The backs of the niches will be covered after installing the drywall on the other side (closet) of the 'wet' wall -- I guess the Hardi can be glued to the back side of that drywall?
But some of the niche meet-ups are larger than 1/8". These larger voids are why I was concerned about following Ardex instructs that yak about using 8+9 to fill all Hardi voids with their membrane and fg mesh.
Your comment (below) about filling in all the joints with thinset and fg mesh makes me feel more confident about what I propose. I just hope I can overcome the big gaps with some stability. Perhaps the 8+9 over all that will go a long ways in holding it all together

The Ardex package directions indicate that the Hardi seams and corners be filled and mesh-taped with the 8+9 -- no mention of pre-filling with thinset. But some of the gaps in the Hardi are large (about 1/4" at the niches for example). So what I propose to do is to first simply fill the Hardi with thinset and mesh-tape (as normal) then treat with the Ardex 8+9 as I did using the AquaDefense on my previous tub surround project. But my uncertainty here is with with the treatment of the corners as with the possibility of 2x4 stud movements. So, do you think the option of fully thinsetting the Hardi first would have any merit? As an aside, I've used Schluter eke for corner tile movement before and it seems to have worked as well as silicone.

Do you have stucco mesh? Any Ardex X32? Ardex S14? Your waterproofing product should not be asked to seam gaps in your wall board. This is crazy to count on the waterproofing to add structure. Board. Tape with ideally a 4" mesh on the inside corners and a 6" tape on the outside corners. Small batches of rapid set, self curing thinset like the S14 work well. X5 and a few days cure time before waterproofing works to.

Yes, I got some galvanized expanded metal for the mud floor. Is this what you are referring to? I was planning on continuing on with Ardex X5, then X77 for the large format tiles we plan to use in the shower. We also got some stiff fg mesh cut to 10" wide x 20ft long (that was for the 8+9). And of course, some alkalai-resistant 2" fg mesh tape I used from the last bath project (on the seams of the Hardi).

Also, can the Kerdi be glued together successfully using the 8+9, or should I stick with the X5 or even Kerdi-fix? ..I'm not sure of your results as your review has yet to be finished.
And if so is there any advantage of just continuing the 8+9 over the whole Kerdi covered pan as a backup waterproofer? -- will it stick for the long term?

I asked Dale Kempster (<DKempster@schluter.com>) what the equivelent of Kerdi Col is and was told it was Ardex 8+9. I have done a lot of testing and multiple products with Ardex 8+9 and Kerdi Corners, Kerdi DS and Noble Seal TS. All my testing has resulted in sucessful installs. All projects and test boxes where flood tested, my last for almost four days. Not a drop of water lost on any. The test boxes when finished we like to break apart. Some simple tests with liquids allowed us to use hand strength only to demo. The Ardex boxes require a good boot or two from the steel toes. Pretty impressive. Both my apprentice and I love the stuff. The X32 is pricey but so worth it. The 8+9 has been around for twenty years.

I guess that's what I wanna hear, John. I cannot afford to do test batches with expensive 8+9, only to then throw it out. It's why I've come to this site to see what the pros have discovered. And it seems like you have succeeded in satisfying the research.

Go to the UK or German Schluter site and watch their installs. Ask yourself why they use Kerdi Col. Then email Schluter and ask if you can buy it here or what the North American equivalent is. Then email Ardex and ask about their ten year warranty with Kerdi - that's twice what Schluter will give you. Why do they double Schluter's warranty? Perhaps because it's twice the system. I alwyays hated the "Air of Bad Blood" I picked up on when my Mapei rep and Mapei tec's bitched about Schluter. Does not give me a warm fuzzy feeling when the setting material company I was using dislikes the Schluter product. Then I stumble upon Ardex and not only do they play nice - the warranty is double. This is a no brainer.

I've also wondered about the constant conflict some have had with the "us vs them" approach too. Both Ardex and Schluter are European products and they seem to make nice with one another there. It only appears to be a semantical problem here in NA -- go figure.

The first time I heard about Ardex was from another Schluter rep at Fontile. We where debating exterior decks and he mentioned the long history overseas with Ardex and Schluter. This rep mentioned something about better technology and I passed it off as a tiss at Mapei (I was wearing a Mapei fleecy at the time). Then I start seeing Ardex bags on so many job sites. Not low end reno sites but multi million dollar homes we wear on. HMMM. Then the kicker is the owner of Quick Drain and I where out for lunch and he tells me to try X32. I did and I love it. This coupled with my Mapei rep pissing me off was all it took to switch setting material companies. We are very happy we made the change and love all the products so far.

I first heard about Ardex from the front end guy at the local supplier. At that point I had just discovered Kerdi for shower building. All the competitors (Prova, etc) were using modified thinset for essentially the same type of cloth membrane, and only Schluter said NON-modified -- wtf. The counterman suggested the Ardex thinset (X5 in my case) for use with everything tile ..including Kerdi. He told me Ardex officially endorsed its use with Schluter products. I used it in my first bath project on the large marble wall tiles and it was so nice to use (at least for this amateur). Then it was kinda reinforced for Kerdi use on various online forums.

I have yet to test their grout and have been told they are still fine tuning this for North America. I have been told that Mapei's Ultra Colour Plus can be used in lue of Ardex's products but you better confirm this yourself. I do not have this on paper or by email as yet.

The only grout I have used has been from Mapei. It seems good. However, again my researched opinions said to stay away from the Ardex grouts.

After resolving this, I also want to include building of a proper (low profile) curb. I figured I'd build it out of formed concrete. Is there a cationary method to use in doing this? I would also cover this with the Kerdi cloth ..and perhaps with a coat of 8+9 as well.

We like to use bricks. Rapid set thin set. This way the product is good to go the next day and not curing for 4 weeks.

What! I would have to wait 4 week before covering it? I figured that by pouring a curb I could better control the design, especially if I reinforce it with small rebar or expanded metal mesh.

Good Luck. Send me an email or call if you more questions. Give the guys above an email and confirm my posts.

I can not say how well the process of seaming the Kerdi with 8+9 will hold up long term and my hunch is that perhaps the safest bet is to install the Kerdi the way Ardex outlines and if you want added protection to then use the Ardex SK mesh and NOT Kerdi Band for the second seam. The SK Mesh rocks and has holes in it to allow the product to lay down flat with no air bubbles trapped underneath.

I asked about something other than open-weave fg mesh tape or bands as you suggest but local suppliers only have the fg stuff.

I strongly advise you to do a test box with the Ardex 8+9 and purchase the proper paddle to mix it with. A test box should be preformed with any waterproofing system.

That is a good idea, John. But still, given the cost of the 8+9 I don't want to break open the sealed box just for a test run. I would think all that [testing] has been covered in this forum?? That's one of the reasons why I'm here
As for the paddle, I can only find the legacy-types like the one in the link above. And they seemed to mix thinset quite thoroughly.

[jadnashua]

For a homeowner that doesn't have to deal with lots of tradesmen stomping around the construction site, the thickness of the membrane is not that big a deal. It also makes for less buildup in corners and overlaps. For a typical residential install, the difference in permeability is not generally a factor either. Once you cover it with tile, the thickness is irrelevant - is 1/8" glass more waterproof than 1/2" plate glass? Is one stronger, certainly, but at what cost. Prior to tiling, ANY membrane, paint on or sheet should be protected on the floor. If the backing material is solid, the walls pretty much take care of themselves. Use the stuff you have and don't worry, just be considerate of the material.

[johnfrwhipple]

When you use the Ardex products with Kerdi you no longer need Schluter for the warranty. Ardex covers it and yes it is approved here in North America. You can not call Schluter and ask because they have nothing to do with it. Call this guy.

Robert Russell. Ask him to email you the specifications for the ten year warranty.

1 (403) 801-4681

Robert.Russell@ArdexAmericas.com

I have the warranty info on file from Ardex. You should too. Just call or email Robert - he will get it to you.

The gaps in your backer board are large. How is the deflection at those seams when you press on the board? I would have wanted to see some blocking between those sheets. If you can tape the seams like you would drywall but use some of the Ardex S14 or X5 with a large stucco mesh strip cut to 4" you will greatly improve the strength there. Also scratch coating the walls with the X5 will extended the working time when you install your Kerdi.

Knowing what I know and having seen first hand waterproofing products fail under flood tests it's silly to skip a test. You can not control how these products where shipped and stored.

Do the tests. If the product does not preform then get new product sent to you. The paddle you show is not similar enough to the Ardex 8+9 paddle. I'm getting a few paddles made for me custom by my metal man Jim. We are going to scale the large paddle down to a smaller size.

If your not in a rush stand by another week and I'll sneak my wife's hand mixer out of the house and into the shop for an experiment.

The 8+9 is only $70.00 for a box. The cost should be a none issue. What is this bathroom costing you all day? $20,000 $10,000 $60,000 You should not be concerned about a $70.00 expense here.

"When it's perfect. It's good enough." JW

[Daler]

Good points you made here, John. There are only a few areas of concern regarding the gaps. And yes all the corners and seams are supported by blocking -- there is NO deflection anywhere. Now, I did not go to the extent and block every Hardi edge including putting blocking laterally ..that is, between the studs and along the bottom edges of the Hardi. They are however, supported 16" oc. In fact the back pony wall was built 12" on center.
The only real concern was one corner where I forgot to extend the stud a bit more from the corner. So I had to run the screws in on an angle to catch the stud ..and still be at least 3/8" from the Hardi edge. The board is seated well on the existing stud though.

I guess the boards could be taken down and rehung a little closer together, but that would still provide a gap at some other location. Another alternative would be to yank them and recut some new ones. All a BPITB. Your idea of mudding using some fg stucco mesh seems most feasible and I will use that to beef up those corner gaps and breakouts.

To reiterate as appears in one of your other threads, when you did that full shower with 8+9 you actually thinsetted (with mesh) all the Hardi seams and corners before applying the 8+9?? If so, then that's what I will do as I agree that it makes less sense to just fill with 8+9 (and mesh) alone.

As for scratch coating, that will be done when the seams are all taped -- thanks for that tip. I remember when the main bath surround was tiled with 12" marble, it took some practice to finally get the thinset to stick as the Hardi was so thirsty. I wound up pre-wetting the surface.

And as for testing the product -- ok, you convinced me -- I'll follow some of your examples and test the product before use. Yer right, this is a one-shot attempt and I don't want to regret it later
BTW, as an aside how much area does a box of 8+9 actually fully cover? ie, will one box be enough for a 3'x5' 3-wall (to ceiling) compartment?

Regarding warranties ..methinks the replacement of Ardex materials might happen, but I doubt any labour, other materials, structural damage and the fact I am not a pro will most probably preclude any claim I might make So, I'm not too worried as long as I'm confident everything has been covered here.

I will look forward to your "hand mixer" test soon. If your hunch works out then we can drop by a local thrift shop and pick one up ..providing they use the same type beaters

[johnfrwhipple]

Thrift Store mixer. Now that is an idea. I know if I sneak my wife's out she is going to kill me if I get caught. It would be my luck the morning I do the test she decides to make Pumpkin Muffins.

You will get about 70 square feet of coverage over Hardie Backer.

I'm going to quiz you now before I answer your question.

What is the number one reason for tile failure?

Before waterproofing or tiling you need to know this. So Daler what's the answer. No helping Jim!

JW

[Daler]

Thrift Store mixer. Now that is an idea. I know if I sneak my wife's out she is going to kill me if I get caught. It would be my luck the morning I do the test she decides to make Pumpkin Muffins.

..but they will be waterproofed I just saw some new ones in XS cargo for $10. Beaters looked rather puny though. How thick is this stuff and will the handmixer be able to move it around?
I still suspect the princess auto mixer will do the trick ..I've even seen very similiar but smaller ones in the $store.

You will get about 70 square feet of coverage over Hardie Backer.

I'm going to quiz you now before I answer your question.

What is the number one reason for tile failure?

Before waterproofing or tiling you need to know this. So Daler what's the answer. No helping Jim!

I'll bite... poor bond? so, housekeeping -- making sure the substrate is clean, no dust. Meh, I was gonna vacume then lightly wash everything down anyway

JW

I suspect this thread may now be at risk of being hijacked by my own concerns. If need be it can be moved to another topic ..just lemme know where

Are there any special concerns regarding the installing of large format tiles on the shower walls (ie, 12x24 & thinset considerations)?

And for traction, we are thinking on putting in a natural 'sawn' pebble shower floor. To get full coverage/bedding of those rocks, can they just be fully embedded in gray thinset (like Ardex X5) without any topical grouting? Would it be best to be taken off their mesh backing and installed one at a time? What about water puddling?

Also, I'm thinking on ordering a Better Bench from Amazon.com. I've read that they are the cat's ass for a nice simple easy-to-prep in-shower seat. What's your experience with them?

[johnfrwhipple]

As long as we keep talking about Ardex 8+9 the thread has not been hijacked.

Once you know the number one reason for tile failure you will approach every step forward with more care. It is one of my goals this year to teach my apprentice more theory and not have so many rules. If he understands why I have so many rules he can use this knowledge in multiple trades.

There is a lot to absorb and lots to learn.

So Daler. Once again - what is the number one reason for tile failure? You had it above.

The number one reason for tile failure is "Bond Breakers".

This is so important to remember. It also the number one reason for a waterproofing failure in my book. You need to clean and vacum the HArdie board. When you have it clean. Clean it again. Then tape with thin set and mesh. Leave this overnight with the S14 or three days with the X5. The scrap with a 3" taping knife and vacuum. Then clean. Then clean again. Then waterproof with the 8+9.

Every step of the way you need to consider bond breakers. Your tile order should be shuffled and all cleaned. Then again before setting clean the backs. Do not have lots of water so wipe the cut tiles and let sit so they are clean but not wet.

Bond breaker. Bond breaker. Bond breaker. I drill this into my appretice's head.


Your question on thinset considerations is a timely one. I just got permission to share some scientific testing on the subject but have not had time to blog about it. I will soon.

I've never used a better bench but have seen them at Ames Bros Tile. Looks like a very well made item. Will your bench be a floating one? If your waterproofing this bench you need to tie it into the walls and floor. The Kerdi inside corners can be flipped upside down to do the outside corners. If you order the Ardex 8+9 order a roll of the SK Mesh.

AS for the stone pebbles for the floor I'm finding that many suppliers are producing sheets that fall apart when soaked in water. We will not install an sheet tile until it has past a soak test.

Do you have a sample of the floor tile? Get it in some water. Leave it two days. Remove tile and let sit for two days. What happens? You might notice rusting. You might notice an odor from the glue. The tile (stone rock etc) could just fall off the sheets. If any of the above happen you should abort your plan or remove rusting stones and loos set. You might want to grade the stones into 3-4 heights for loose setting. I recommend using a 3-4% grade for this shower base. Stone floors always drain slower.



Here you can see an install with Ardex 8+9. I used some Ardex X32 when taping some large gaps and made the mistake of using it out in the field as well. The Ardex X32 is my newest favourite thin set (in fact it's a thin set, medium bed and thick bed thinset all in one) and discovered because of the larger sand particles very hard to cover with the Ardex 8+9. In the end I used 3-4 coats to get proper coverage.

The S14 rapid set has a silky sand and lays down nice and flat.

We started skimming out our walls after we went back to re-visit a job where there was some design changes. I noticed that when the framers pulled down some studs and in doing so damaged the wall board the waterproofing that was attached to the taped and skim out areas bit much better. Since then we have been looking into the bond strength of these waterproofing products over Green EBoard, Wonder Board, Hardie Board and in all three the waterproofing bites better to thinset than it does any of the backer boards. When thinset cures it grows crystals that help further lock it into the substrate.

If these products are designed to be tiled it is crystal clear thin-set bites to them. This bond is stronger than the bond to your backer board. So because of this logic we now skim the walls out. This skim coat needs to be done with skill and care. Burn the thinset into the board. Move the flat trowel in six directions and lock it in.



This is an older shot from summer time. The waterproofing is Mapei Aqua Defence and you will notice the different colours. Where it is darker it is nearly dry. Drying before I can even finish coating out the shower. Now speaking of theory look at where I taped the niche and skim over the screw heads. The product is still drying (you can tell because of the lighter colour). Now if we know that the thin set is modified - we do because I rarely use cheap unmodified thin-set and that the Aqua Defence is still curing what have we learned? I think the modified thin-set slows the cure time of the Aquadefence because it is slower to absorb moisture.

Now with any product cementious based you do not want a flash cure. This makes for a weaker bond. So my theory of skimming out these walls slows the cure a little and I think makes for a stronger bond. The board needs to be cleaned and the first coat of waterproofing should be a burn coat where it is forced into the pores of the thin set. I would roll the first coat and right behind it flat trowel it tight. Your second coat can be rolled but makes sure the first coat is stuck tight. We do not coat this first burn coat as a coat. So we apply two coats over top - crossed laced with the roller.


JW

[Daler]

....................

As long as we keep talking about Ardex 8+9 the thread has not been hijacked.

Once you know the number one reason for tile failure you will approach every step forward with more care. It is one of my goals this year to teach my apprentice more theory and not have so many rules. If he understands why I have so many rules he can use this knowledge in multiple trades.

There is a lot to absorb and lots to learn.

So Daler. Once again - what is the number one reason for tile failure? You had it above.

The number one reason for tile failure is "Bond Breakers".

This is so important to remember. It also the number one reason for a waterproofing failure in my book. You need to clean and vacum the HArdie board. When you have it clean. Clean it again. Then tape with thin set and mesh. Leave this overnight with the S14 or three days with the X5. The scrap with a 3" taping knife and vacuum. Then clean. Then clean again. Then waterproof with the 8+9.

Agreed. It was intuitive with me last time. Everything was super clean with the last project as it will be this time too. It's good that you reiterated this here

Every step of the way you need to consider bond breakers. Your tile order should be shuffled and all cleaned. Then again before setting clean the backs. Do not have lots of water so wipe the cut tiles and let sit so they are clean but not wet.

Bond breaker. Bond breaker. Bond breaker. I drill this into my appretice's head.


Your question on thinset considerations is a timely one. I just got permission to share some scientific testing on the subject but have not had time to blog about it. I will soon.

Along with your mixer results, as long as it's not to distant (we gotta get on this soon) I will look forward to reading about your thinset testing results too

I've never used a better bench but have seen them at Ames Bros Tile. Looks like a very well made item. Will your bench be a floating one? If your waterproofing this bench you need to tie it into the walls and floor. The Kerdi inside corners can be flipped upside down to do the outside corners. If you order the Ardex 8+9 order a roll of the SK Mesh.

Yes, the bench I have in mind is the floating corner one: BB30. And I am planning to encapsulate just the bench in either Kerdi or 8+9 or both (if your tests prove out) According to what I've read it can either be mounted to the Hardi and tiled around it or mount it after the tiles are up to give cleaner lines (and less micro-cutting). Jury is still out on either method as I have no experience with it.
I guess the SK can be special ordered but a roll is way more than I will ever need and it is expensive. Can I not just use some heavy duty fibreglass mesh (similar to dw mesh tape but bigger holes and stiffer) cut into appropriate strips? I've got plenty of that.

AS for the stone pebbles for the floor I'm finding that many suppliers are producing sheets that fall apart when soaked in water. We will not install an sheet tile until it has past a soak test.

Do you have a sample of the floor tile? Get it in some water. Leave it two days. Remove tile and let sit for two days. What happens? You might notice rusting. You might notice an odor from the glue. The tile (stone rock etc) could just fall off the sheets. If any of the above happen you should abort your plan or remove rusting stones and loos set. You might want to grade the stones into 3-4 heights for loose setting. I recommend using a 3-4% grade for this shower base. Stone floors always drain slower.

Reassuring advice, John -- thanks. We were into Tile Town recently and they showed me a sheet of the stuff. Any of those items are special order multiple sheets so getting a sample is not possible.
It looked like the pebbles were very crudely glued on to a double mesh using glue sticks! As usual, I found that the more paid, the better the product -- and there was a huge spread in costs. The dealer also suggested soaking it first. And as you suggest, taking them off and thinsetting them each one separately. At least that way there is some assurance of full base coverage. On the mesh it looked like the pebbles were much too close for any grout to migrate fully between the stones -- hense my thoughts to just thinset the heck out of them individually and skip the grout. But now that opens up another concern about thinset "open" time when laying those rocks -- I can see myself being very anal about setting each individual pebble just right and feeling rushed before it sets up. How can I get around that (ie, with X5)?

JW

[johnfrwhipple]

Daler use the proper mesh (SK Mesh) for the 8+9. A roll is under $20.00 I think.

If you need a part roll I can send it to you. Let me know how much you need. If it's a half roll I'll split the cost with you. I go through the stuff like Kleenex.

JW