Hello Chaps, I use Ardex NA on practically everything! old latex with old glue, bitumen, ply, ceramics, whatever. Is there products which you can trust to do jobs like these but cheaper and reliable? I have used others in the past and sometimes it can sound hollow or cracks! I prime even on NA, think it flows better and have longer working time. Good to hear what others suggest, Cheers.
I use CL when allowed and NA when it's needed - both depending on the subfloor but also use 300hd when possible, love that stuff and seems to flow best for me out all screeds. I always prime with NA also but not when I'm using a dpm sandwich system. There's plenty out there for you to use and NA isn't the cheapest so I won't use it when I don't have to. I'll mainly use CL/300hd and recently started using renovation for my ply fits.
I only use NA if there’s no other option Never known it to fail but the flow isn’t great even primed If you’ve had hallows or cracks you’ve used something with a compression strength that’s to high for the subfloor or what ever you’ve gone over NA is a very low compression strength so very little pull on the subfloor as it dries and stick like s*** to a blanket That’s why it works Water based are very high Compression and yield strength so as they dry you get a lot of pull so if its over something soft it will crack to hell so only realky suitable on solid clean slabs with no contamination I tend to use a lot of Ardex CL the C.S. Isn’t to high and it flows really well
what about over old screed and adhesives, i was told by ardex rep its only meant for fresh screeds or grounded back! (f**k that!)
You shouldn’t go over adhesives with anything only residue Most are water soluble I grind everything off unless an existing screed is bonded and solid but I test the compression strength first so I know what I can use over it
If the subfloor is dry and you want low stress and good flow look at some of the gypsum levelling compounds. We use them over bitumen and old adhesive all the time. Sent from my iPhone using Tapatalk
Unfortunately adhesives don’t like sticking to gypsum based compounds They barely hang on especially PS
Na is a no brainier on bitumen or asphalt. Otherwise it's a Bit of spit and prime . Then whatever 2 part is on offer . never had a problem yet .. touch ply ! Sent from my Moto E (4) Plus using Tapatalk
You sound like the man with all the gear! fair play I would love to grind everything off but no one ever speaks about grinding and just dish out NA instead or level it bond if your unlucky!
Personally not a fan of grinding floors as most old adhesives have asbestos in and concrete has silica in which is cancerous. Get some decent extractors and masks of your doing it on the regular Sent from my iPhone using Tapatalk
Definitely don’t grind bitumen for those reasons Those are the situations when it’s NA or Tilemaster Super 30