Jay, the specs they provide you are the minimum that product should reach. So if mixed on the higher ratio then that will be the spec. If mixed with less water then it should be a bit higher. :thumbs Sidney, if you speak to manufactures they will recommend what "number" the screed should meet for there product. For instance, if your glueing down a wooden floor the compound under it needs to be above 30N/M ! Off the top of my head i think most lino , LVT , Vinyl manufactures state 20N/M and above. Im not sure on that one tho. Also to add, you cant screed over a product that has a lower compression strength than the product you want to put down. The product already on the floor should be removed which will obviously be a nightmare! This is why careful consideration to what product is used is important as you need to think of what may be used in the future. I would always advice you try and use a product with high strength to start with.
But if the above is true, you're saying you can't use ardex na (16n/m2) under vinyl (30n/m2)?......that can't be right, surely!
Yep that is correct, if don't believe me ring the BWFA and ask them. As for vinyl im not sure of what is recommended as i said. I will try and look it up for you. It all comes back to you not supplying a product sutible tho. For instance, you would not supply a laminate floor to the bar area of a nightclub! , you would not fit a felt back carpet to the stairs of a busy hotel. Its no different to the compound under your LVT flooring, you have to supply a product sutible which in my personal opinion 'NA' is far from sutible.
This is what I've been sayin for years the structural integrity and compression ratios of any screeding compound is only going to work if whats underneath it is equally the same or stronger. How many of us have seen poor and soft concrete sub-floors. Try telling that to a customer or builder that their whole sub-floor needs to come out and be re-done and you'll just get laughed at or as they usually do think we are trying to pull the wool over their eyes.
If all that is true, then what exactly is na for?......it seems to me, from what you're saying, it's not even suitable for walking on tiptoe in silk slippers, and yet I've never had a comeback friom it!....Has anyone else on here had problems with it?
Also I have a question for all regarding a faliure I recently found out about. A friend of mine was asked to quote on an installation of solid walnut to be glued down all over. He quoted and the customer decided he was to high for the installation but did accept the figure for the screeding. So he took on the screeding work asked for fballs to advise on product to be used, he followed their spec to the letter. And guess what the floor failed popped and pulled the screed up with it now he's being taken to court and blamed. F balls are standing by him and have inspected it and said there is nothing wrong with their product and he has followed their in structions implicitly. The customer got someone in to inspect and advise whos to blame and he pointed the finger at my friend. My friend had someone else do an inspection, this person asked a few more questions and found out that the floor was installed through out the entire ground floor, with no break offs for expansion upon removing some of the skirting he noted there was no room for expansion. He also found out that the walnut was installed without using the washer gaps as recomended, and the installation was carried out by a close family friend who has only ever installed laminate yes laminate in his home. I have to ask why is he to blame as he did not install the walnut and was only contracted to screed, and why is the person who is on the customers side saying its his fault clearly that person has not got a clue and should investigate closer.
NA is sutible to be laid under a domestic vinyl in a domestic property. NA is what most fitters like to use due to its easy to sand etc. Its what a lot of fitters in the trade ask for. BUT....it should never be used under a solid wood floor that is being bonded, it should be carefully speced in a commercial situation. This is the reason why Ardex make more than one product. They make other products sutible to the area you are installing in. Why else would they have other products if NA was sutible for them all? They wouldn't . There is nothing wrong with NA if used in the correct area. However, like i say. Always try and over spec the job to future proof yourself.
Yeah but for the most part the spec comes from the architect try gettin him to change his mind, you'll have a better chance of banging gripper down with your hands intead of a hammer.
I'm gonna have a chat with my old man, as I remember I was only very young but during sunday lunch the topic of disscusion between my father and grand father was latex screed at the time and it was a new product. My grand father was not impressed in his words I remember him clearly saying thats it you watch this stuff will take the place of the skilled masons and concrete finishers their quality will now go down hill and all the making good and putting right will now be our job and their skills will be lost for ever.
PM me the inspectors name Jay and i will look into this for your mate. If what you have said is true then it sounds like the person inspecting has not inspected correctly. However this may not be the case and the inspector may just be very clued up on "how wood works" and calculated the forces etc of the wood on the compound. I take fball Have tested his screed and come back with the ratio etc that it was mixed at to prove compression strength to back him up? If they dont have solid proof then there back up will not stand up. Every thing has to be proven mate.
Phew!!!...I was getting worried, there, na is all I ever use, but I only do domestic! ....As for Jay's walnut/screed point, I don't do solid wood floors so I'm no expert, but I thought they shouldn't be stuck to the subfloor (unless secret nailing to batons)? It stands to reason that if you stick it to a screeded floor, the screed will blow due to the expansion/contraction of the wood, regardless of whether or not the expasion gaps are correctly placed?
Only problem vie ever had with ardex is having a big delivery of na and a box of normal liquid got mixed in to it and we didn't notice until it was in the bucket, learnt a lesson that day check all deliveries and never put ardex na with yellow bag liquid set in the bucket in about 2 seconds flat
You can stick solids to screeding compound s all day long mate, you simply have to use the correct compound. Tell you what mate, it would be great to get you down to one of our courses where you can try out the products yourself. Infact if you want to go to Mapei and have a FREE course let me know. Get to try out the products yourself.
PM me the inspectors name Jay and i will look into this for your mate. If what you have said is true then it sounds like the person inspecting has not inspected correctly. However this may not be the case and the inspector may just be very clued up on "how wood works" and calculated the forces etc of the wood on the compound. I take fball Have tested his screed and come back with the ratio etc that it was mixed at to prove compression strength to back him up? If they dont have solid proof then there back up will not stand up. Every thing has to be proven mate.[/quote] F balls have done their home work and have proved that the screed and method is not at fault with documents to back it up. I don't need to PM the name i have edited your discription of who teh person is Jay, basically because people will start to be guessing and as this is a court case that is on going as you say why is it the person who installed the walnut who is clearly not a certified installer and fitted it all tight to the walls not leaving any expansion and did not allow for the washer gaps not to blame.
i dont know mate, i have not seen the floor in question so cant comment. But im sure if FBALL are backing him as suggested then your mate has no problems. The name of the installer has been requested Jay as the inspector in question and Fball dont know what your talking about. Could you PM me you friends name so i can check for him. After all if a mistake has been made it needs to be sorted for your friend.
