Anhyfix fail on ditra matting

[Chris Gibbs]

Hi everyone. I have only just seen this thread so my apologies for the delay in replying. Firstly, I would just like to say that Anhyfix has been around for several years, in that time we have installed hundreds of m2 worth of tiles successfully onto anhydrite screeds, many of them installing an uncoupling membrane, Ditra Matting, Dural CI++, Tilemaster Anti-Fracture Mat and several other systems.

Tilemaster Anhyfix does get a gradual bond to the underside of any uncoupling membrane, equally if the same test was done with a cement based adhesive, a similar thing would be seen. The bond gets stronger as time develops, and as Mark at Imperial has mentioned, try pulling the mat up after 48 hours and the results will be much different. In testing we have done here, we have applied Ditra Matting, Dural CI++ Matting and Tilemaster Anti-Fracture Matting, with C2, S1 and Anhyfix adhesives, we were extremely surprised to learn that the best bond strength we got was from Anhyfix across the board, with all three mattings that were tested.

We know that certain products are only guaranteed with a C2 or cement based tile adhesive, however for us here at Tilemaster, we know that when installing onto anhydrite/gypsum based screeds, a gypsum based tile adhesives delivers a more satisfactory result, both that the products are 100% compatible but also that we are able to deal with slightly higher moisture content that may remain within the screed.

If the manufacturer of the uncoupling membrane will not guarantee their product with Tilemaster Anhyfix, then providing the screed has been prepared correctly, Tilemaster Adhesives will offer the guarantee.

That's very kind of you to respond, and giving the fitter peace of mind. We all care about the work we do and it's good to know we have the backing from the manufacturer too.
Thank you.

 

[Time's Ran Out]

1. We've ever had a problem with Tilemaster adhesives.
2. We've never had a problem with Ditra.


@jcrtiling - Bal limestone is notorious for shading ( I won't use it anymore).

 

[LM]

Surely your leaving yourselves open to guarantee issues if you don't use one suppliers products.

schluter/Dural don't make adhesive obviously so we're forced to use a different manufacturers products. I think a bit of common sense would keep you right here. We could do a test ourselves with different mats and different adhesives on different backgrounds and try to pull up at different times/stages and trust your findings

 

[Glynn]

I've decided I must of had a bad bag or so of anhyfix.., tried it again from a different pile today and it was lovely, smooth, creamy and spread like a dream, pulled back the ditra and bingo... TOTAL COVERAGE!
They have batch numbers on the bags. Does anyone know how to decipher these please?

The first 6 digits of the batch number relate to the date manufactured and the last 2 digits are the batch that day. We keep a retained sample of all the batches we produce for six months so if anyone thinks there is an issue we can retest the retained sample. If anyone does feel that they have an issue with a product we take it has our duty to do a full specification test if you can give us the batch number. I was part of the team that tested Anhyfix with the de-coupling membranes and it came out top from all the adhesives we tested it with, and like Mark said it gained its bond over a couple of days.

 

[Flintstone]

Glynn is it true that Kerakoll have bought tilemaster ? What does this mean for us?

 

[Glynn]

Thought this thread is about Anhyfix

 

[Flintstone]

Ha ha, I'll start a new one!

 

[Mark Frost]

it is true lol

 

[WetSaw]

By the way, he'll be known as Glynnio from now on....

 

[Lodger]

Zero adhesion... I'm following schluters advice and going with the ardex. Can't remember the exact one... x7 I think. I will post the primer and adhesives tomorrow.

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Hi,
Looking at the anhydride screed on the picture the laytance hasn't been removed. If it's shiny then it's not scrubbed down enough.
Best way to prep the floor is to use a copper scrubbing disk or carbon stone pad on a floor cleaning machine to scarify the surface at least 1mm so you can see the poores of the screed. It should look like the edge of a plasterboard. Best to do it no longer then 1-2 weeks of screed going down or it's very deficit to scrub. The surface tends to harden over time.
Removing the laytance considerably reduces drying time.
Then use an airhydrometer available from Fball or make your own to check the floor is dry enough (85% relative humidity) before using any tiling primer 1-1 for first 2 coats then a neat coat. Primer must be dry before each coat.
If you follow these steps then you can tile straight onto the screed. No really need for decoupling mat. Not even on UFH screeds. Decoupling mat is a belt and braces approach. Use any S1-S2 type adhesive to fix tiles.
Main point is to make sure the screed is DRY.

 

[Dumbo]

I thought you were looking for a minimum 75% rh for tiling and i have a feeling that somebody who should know ( i think it might of been @Ajax123 ) said there was no evidence to support that by removing latence you decreased drying times

 

[Ajax123]

I thought you were looking for a minimum 75% rh for tiling and i have a feeling that somebody who should know ( i think it might of been @Ajax123 ) said there was no evidence to support that by removing latence you decreased drying times

Correct on both counts

 

[Chris Gibbs]

The first 6 digits of the batch number relate to the date manufactured and the last 2 digits are the batch that day. We keep a retained sample of all the batches we produce for six months so if anyone thinks there is an issue we can retest the retained sample. If anyone does feel that they have an issue with a product we take it has our duty to do a full specification test if you can give us the batch number. I was part of the team that tested Anhyfix with the de-coupling membranes and it came out top from all the adhesives we tested it with, and like Mark said it gained its bond over a couple of days.

The bags have been burned on the fire so no way of finding out the batch numbers, although I did manage to take some photos of the problem mix against a good mix... the bad was really crumbly, weak and dull in colour against the good mix

 

[Lodger]

I thought you were looking for a minimum 75% rh for tiling and i have a feeling that somebody who should know ( i think it might of been @Ajax123 ) said there was no evidence to support that by removing latence you decreased drying times

I think it's that kind of subfloor that people have different methods of prepping the floor.
Everyone seems to raise an eyebrow when anhydride subfloor is mentioned.
For me it's just an educated observation regarding the laytance. If you were to seal the pores of any screed holding any moisture within, then it's going to take a long time for the moisture to escape. The Laytence on anhydride screed, imho is blocked pores.

 

[One Day]

Alaaaaaaaaaaan!