Ardex 8+9 Product review for 2012
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.
Gassing in Ardex 8+9 - Tiny pockets of air
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!
Irridescent layer on Ardex 8+9 - film layer on flood test
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?"
Ardex Schluter ten year warranty
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
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
Mixing Ardex 8+9 with a mix master
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!
Hardie Board and Ardex 8+9 - watch out for bond breakers
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.