Just to clear a few things up. Asphalt = black / brown and dents easy with caster chairs. Cracks if nailed into. THIS IS A DPM ! so if damaged the dpm will not be working. Yes it can be screeded over with a low strength compound. Ardex NA is perferct. IT MUST BE DEGREASED and light sand. Magnesite = red / pink colour BUT colour pigments was sometimes used. It has wood, sawdust and Asbestos fillers. Very rare to find after 1960. This floorcovering can not be prepped nore can it be covered. It breaks down with age and releases chemicals that rots metal work like plumbing. It should always be removed. LVT Click= the subfloor prep has to be very good. If not teh header joints unlock after a few months. It also can only be used on floors below 75%rh (Mflors can be used up to 85% RH) . Yes it is plastic but has fillers in the center cores that can be effected by moister (warping and cupping) . Also you shouldnt lay direct onto Ashphalt as it contains bitumen which can react also. Also be aware of products that say no expanstion. Even teh ones with teh fibre glass cores. We have the test results back form the labs from a few different LVT products that may surprise !
Christ confused now, so its most likely aspahlt not magnasite........what are my options with out digging the floor up ??
Jumpax, isolator, etc. All depends on condition of subfloor. Also you dont have a guarranty on isolator with LVT glued to it. It works fine but to many people cock it up so they simply say dont use it.
Ardex overview on it... http://ardex.s3.amazonaws.com/tech_bulletins/tb078.004_overlaying_magnesite.pdf
ok so if i take a reading of the rh apply the appropiate dpm if over 75 then latex i can vinyl the floor still ?
Polyflor.... 2.7 MAGNESITE / GRANWOOD FLOORSComposition floors which are composed ofmagnesium oxychloride cement or polyvinylacetate/cement are highly absorbent. As such,if overlaid with an impervious material, theycan break down due to the effects of risingmoisture, as the majority of these floors do notincorporate an effective DPM. In all instanceswhere the material is laid directly to ground,Polyflor recommend that the screed be upliftedand relaid incorporating an effective DPM.For floors that are on the first floor or above,cracks and small hollows should be patch filledand a cementicious smoothing compound of atleast 3mm thickness must then be applied, priorto the installation of the vinyl floorcovering.The smoothing underlayment supplier willprovide details on which product within theirrange must be used to suit the end useapplication and subfloor construction, togetherwith details of which primer should be used
Because it is low risk. Alot of abestos jobs you can do. Just look up the data sheets on their website.
just checked the price on isolater and its compareable with what i was gonna charge him for screeding , so if i laid this down with a sheet vinyl on top , do u need to stick vinyl to it presuming its soft ish, also jumpax never used that would that be the same principle if i used sheet vinyl..........im thinking of cost as vinyl will work out less
If magnesite you cant do any prep and you cant put anything impervious over it. Only carpet. Magnesite is a finished flooring product. Just like a old carpet you remove it before putting down a new carpet. If asphalt then you can screed over. If cracked you should get a asphalt company in first to repair the subfloor and then you can screed over it. Asphalt is the subfloors DPM so it will be below 75%rh apart from if there is a crack.
Dont you have to get it tested first Daz to find out if its low risk or high risk? Also disposal and clean up , and protection to other areas along with own PPE required?
I'm guessing its bad practise as it could still fail if there is a high moisture content and you cover it with vinyl?
