Evening mate, yes apparently it was Ardex CL. No blue in sight, so no primer before the Ardex, assuming you would be able to see it on the subfloor?
ONLY MY PERSONAL ASSUMPTIONS TOPFLOW Screed C will require no sanding to remove laitance but it is recommended to lightly abrade to clean and remove building residue from the floor prior to application of floor covering. The above covers them as in (it shouldn't but MAY need abrading) Ardex may say the same, it's really down to installer to judge how much needs to come off. Looking at your pictures, I would say it needed to come off to a point that the primer would be absorbed into the floor and still be able to help the compound adhere to it. I personally would say it hasn't been abraded or ground off, nor can I see any residue of primer. Also looking at the pictures it looks more like TopFlow Screed A which is anhydrite, just due to someone scraping the top off in one of the pics and it looks a lot of particles once the laitance has been removed, (not to say it has any) Good luck and let us all know the outcome please.
I think its very likely that a primer was used. Most new build companies we work for do supply it. Chances are it will be watered down, and still attached to the back of the latex thats coming up. Its a bit shitty the way Tarmac have worded that, as its almost a given that it should be ground off. I had a flow screed pumped into my own house, over ufh, around 25 years ago. The supplier installing, said I could fit Lvt straight over it, no grinding, no latex, or any other prep. Full of BS
Thing is, all they want to do is get the $ in. Not interested in anything else. Nowadays, they will send a 12 year old to pop in , no vac usually a hand grinder make loads of mess then say it's good to go. Contractor comes in and says no it's not good enough and that is when the arguments come in to play. OR House bashers just lay on it, as it's not their problem they just do as they are told. Seen it, heard it, been there..
They also butcher the screed when they do grind it. Needs a 6mm coat of levelling compound once they've finished.
