kerakoll rep ran a mile be warned

[Ajax123]

As no doubt expected here's my take on it.

Firstly if the job was in Exmouth I'd be surprised if it was anhydrite as there is only 1 supplier down there from Ashburton and I don't think they would go as far as Exmouth. It was most likely hemi hydrate. I stand to be corrected of course.

In terms of the failure it sounds like simple lack of surface penetration. This could have been dust or it could have been surface contanmination or simply that the surface had not been sanded (although I know you are saying it was).

I am not sure about the Kerakoll primer in terms of polymer content but I have seen lots of these types of primers (simple acrylic water dispersed) which need to be heavily diluted to get them to penetrate the screed surface. I don't like these primers personally and agree with TT that an epoxy is better. Usually a water dispersible epoxy diluted 1:1 (e.g. Screed master epoxy). I posted some pics a while ago showing the kerakoll addy but I can't find the thread now. That was laid on an epoxy and there have been no issues at all with that job. The H40 Ideal does seem to work well as I have seen it used with and without primer. Trouble is if the primer don't get into the screed surface it matters not what addy you use cos it will fail.

This one was not an ettringite failure as it happened too quickly. Epoxy works much better against ettrignite when using cement based addy.

 

[Ajax123]

Oh by the way I think if the rep has behaved that way he needs stringing up by his thumbs.....:incazzato:

 

[TT Tiling]

As no doubt expected here's my take on it.

Firstly if the job was in Exmouth I'd be surprised if it was anhydrite as there is only 1 supplier down there from Ashburton and I don't think they would go as far as Exmouth. It was most likely hemi hydrate. I stand to be corrected of course.

In terms of the failure it sounds like simple lack of surface penetration. This could have been dust or it could have been surface contanmination or simply that the surface had not been sanded (although I know you are saying it was).

I am not sure about the Kerakoll primer in terms of polymer content but I have seen lots of these types of primers (simple acrylic water dispersed) which need to be heavily diluted to get them to penetrate the screed surface. I don't like these primers personally and agree with TT that an epoxy is better. Usually a water dispersible epoxy diluted 1:1 (e.g. Screed master epoxy). I posted some pics a while ago showing the kerakoll addy but I can't find the thread now. That was laid on an epoxy and there have been no issues at all with that job. The H40 Ideal does seem to work well as I have seen it used with and without primer. Trouble is if the primer don't get into the screed surface it matters not what addy you use cos it will fail.

This one was not an ettringite failure as it happened too quickly. Epoxy works much better against ettrignite when using cement based addy.

hi again ,thanks for your words ,but the builder and myself did prep the floor by sanding with wire brush ,and with a electric sander with very course paper ,the builder had two guys working on the floor for about 3 days as well , like you said the 2 part is the only way forward , hope i never have this prob again ,put it down to a learning curve ,ie primer not up to the job

 

[Gazzatile]

intresting tale just for info you should use a hygrometer to test the screed this would need to be down for 4 days before being removed this measures the moisture in the screed not just the first 2 or 3 mm a surface damp meter can say floor is dry but if you drill into it water will appear in the hole. We should all learn from mistakes and try and help every one. It is not always the tilers fault but they normally get the blame as they put down the tiles without having been told the full story.

 

[Kia tiling]

I've just started using Kerakoll and I must admit until I read this I was impressed by it, now I'm a little worried!