There is alot of posts on f.ball, mapei & laybond screeds. Does anyone use ardex ( even though the price), uzin, tremco or any of the others?
I use ardex na for the vast majority of my screeding jobs, it's good stuff, especially for small areas, and doesn't need priming. :smile:
According to the spec you can put it on almost anything without primer, the only downside is that it goes off really quick, so it's best to use on a small area, especially if you're working on your own, otherwise you might leave a ridge where your first bag meets the second bag if you see what I mean......could leave you with a bit of rubbing down to do before you lay the flooring
On the screeds, never used uzin, any good? Liked the mapei on the forum day last week. Have used level flex a few times and its good for the low price
Dont need to prime with na mate, but yeah it does go off quick, definatly wanna get the spike roller on that stuff
One of the compnys I work for only use tremco 300 sx I like it nice flow goes off quite quick but drys hard a real arse to rub down if you get a roller stop line but generally ok not used it in a large area yet
Ive used Instarmac ultra level it super30, That wasnt fun. Ive heard some of their other products are very good tho
be careful of products that say you don't need to prime. Normally they state you dont need to prime as there product has very low compression strength. Also some products state you dont need to prime depending on what your bonding to and the subfloor adherence property's. Seriously you dont want to go there, the tests etc to find out if you need primer simply are never going top happen in the real world. Anyway getting back to Ardex NA. Have a look at this - Compressive Strength After 28 days approx. 16.5 N/mm2 Flexural Strength After 28 days approx. 5.5 N/mm2 Now to compare to MAPEI Latex plan Compressive strength (N/mm2): after 28 days: 30 Flexural strength (N/mm2): after 28 days: 10 This is what you need to be looking at. As you can see above, one of the two products is rubbish compared to the other
I don't really buy all that technical jargin its all hog wash, do you know how they come up with those figures in a laboritory in a glass tank hmmm science may be but real world not. I used a Mapei one a few years ago on a 22mm ply floor the rep said it was ok to use, we had to put 10mm down over the top of electric under floor heating the whole lot cracked like crazy paving and curled up under the installed rubber sheet flooring not good so I will never use it again. Ardex K15 is the best I've ever used IMO the Rolls Royce of screeds, RS, NA, and the good old fashioned yellow and black bags, I've used thousands of metres of Ardex and not once have I had a failing even without primmer and over old adhesive residue not a problem. It would always be my first choice especially over quary or ceramic tiles. When I went to their training day the guy their John Oliver I think it was at the time he said shouldn't tell you this but when mixing the yellow and black bag add just a small cup of water to each liquid before adding the powder this will help it to flow.
You wont need water with na mate, it flows out nice, just as some1 said if your mixing on your own or doin big areas it goes off quick
Going to screed it Monday now as 2 screed jobs on so both of us screeding so should help with the goin off 2 quick.
I still found it a little stiff Merit, when doing large areas it is best with 2 of you one mixing and rolling and the other pouring and troweling my mate would always after I got half way through a bay start trowling a new batch alongside what I had already done only a couple of trowel widths so that when I started the next bay the edge was still wet worked like a dream as with a trowel and my go go gadget arms I can spread 2.5m widths.
Adding water to compounds will reduce the strength of the compound. This may not affect most of you on domestic jobs, but commercial for instance it will effect you when some one wheels something heavy over that vinyl/lvt floor or point loads it with a heavy item. Hospitals etc are getting wise on how there floors should preform and yes they test them. If you prepare the subfloor that does not stand up to what the area demands of it you will be liable to replace all the floorcoverings. So may i ask, how many of you have used NA for instance in a commercial property? if so you are now liable to replace the floorcovering! You have basically supplied a smoothing compound that does not meet the regs of most floorcoverings! This is why this 'jargin' of specs needs to be understood and the correct compound installed. Also 'Jay' you say you had a failed floor? did Mapei come out and find out for you why it failed? If a floorcovering fails then the manufactures need to show you why it failed. If its down to them they will replace the product. So what was the issue in your case?
Matt I'll ask the shop who I done it for, it was about 4 years ago now, but it was really strange Matt it was the whole ground floor of a house in Teddington which the customer had chosen rubber sheet flooring and had installed the old heat mats those horrible wire ones. I screeded over all the wires it was all primed as spec'ed by Mapei had to be done in two hits both coats were primed, however the last drop of rubber could not be installed untill 1 month later as the customer was waiting for some special sliding door to installed and it was coming all the way from Italy. When I went back to install the last piece I noticed the cracking and at the cracklines it was starting to curl up and tent and you could see this was begining to grin through the installed rubber. I know it failed but not sure on what the final outcome was as we done it for the builder and he went bust. I know what you're say about adding water and I'm only talking about a very small ammount not flushing a large jug full into the mix and I was reliably informed it was ok for the one I was talking about, some leave a little powder out or add more liquid the only problem with that is you either run out of liquid or have all these bags with a little powder left in them. I certainly don't do it with all screeds just the yellow and black. I mean take the water mix screeds they are saying add 5 to 6.5 litres of water and I'm reading this on alot of bags these days so I have to ask in that science jargin whats the structural integrity of the screed ratio's using 5 litres and what is it using 6.5 litres, theres only one set of figures to go buy for that science but when it comes to the mixing theres 2 sets of figures the science just don't figure, if you're say adding more water will make it soft which is logical then from what mix do they take their figures from the 5 or the 6.5 litre mix.
I wouldn't use ardex na on commercial jobs, but then I only do domestic anyway.......I'm not sure that I give much credence to compression/flex strength ...on the face of it, a "5" seems low, but unless you know what sort of abuse a "5" can take, it's just a meaningless number.......it's a bit like how bs suggests that many pu underlays are ok to use on h/s/l, but experience has taught me to only ever use crumb in those areas......just my opinion :smile:
