Self Levelling over old adhesive - Tile Advice

[reeso]

I've just knocked my toilet and bathroom into one room and discovered the 2 floors are slightly different heights.

I want to use a self levelling compound to bring the (old) toilet side up to the same level as the bathroom.

There has been some form of thin layer applied to the floor to stick the old lino onto which I have scraped away. Now I am faced with some form of old black adhesive. It isn't sticky.

What type of self levelling compound should I use?

Thanks

 

[guy1976]

latex based

 

[sWe]

The black adhesive is probably asphalt based. Be aware, that if old enough, it might contain asbestos. I don't know what british regulations say about that though. If it's ok to just cover it, I'd use Ardex Arditex, or something similar. Make sure to follow the manufacturer instructions of which ever product you chose.

 

[TilingLogistics]

The black stuff is probably some form of old bitumen based adhesive used years ago for marley type tiles.

Kev

 

[sWe]

I think I unintentionally wrote in american english. :stupid:

Bitumen is an asphaltene material. I forgot that in british english, "asphalt" refers to mineral aggregate and bitumen, where as in american english, the bitumen itself is often refered to as asphalt.

So if I say asphalt, I generally mean bitumen.

 

[floydyboy]

The black adhesive is probably asphalt based. Be aware, that if old enough, it might contain asbestos. I don't know what british regulations say about that though. If it's ok to just cover it, I'd use Ardex Arditex, or something similar. Make sure to follow the manufacturer instructions of which ever product you chose.

i cover this stuff on a daily basis and a majority of it does contain asbestos acording to the reports i receive
we us cempolatex self leveling compound,it is bonded to the floor using SBR not PVA. if a thickness is required you should add some sand to the mix to give it body. hope this helps

 

[reeso]

Thanks everyone. I'll buy some Arditex tomorrow. I've got some BAL Prime APD already - can I put some of that down first instead of forking out for SBR??

 

[sWe]

Thanks everyone. I'll buy some Arditex tomorrow. I've got some BAL Prime APD already - can I put some of that down first instead of forking out for SBR??

Here's the manual

 

[Woody123]

sWe

I know this is probably gonna sound stupid but when use SLC how do you know what thickness you have applied (i.e 8mm,12mm....) Do you use the square meterage that you have covered as a guideline or is there something really simple im not picking up on?:whatchutalkingabout

 

[sWe]

Four easy ways of controlling SLC thickness:

• Stick your folding ruler into the SLC. The most obvious way, but useless if the initial substrate is uneven.
• Mark the surrounding walls using a ruler or a tape measure, and a spirit level. Mark a bit higher up than your intended final level with a pen, and work your way around the room with the spirit level, making a line. Use that line as a guide to mark the final level with your measuring tool. Just make sure that you hold it at a steady and straight 90 degree angle. Pour up to the marks.
• Put down some sort of level guides (nails for example), and make sure there level with you spirit level. If they're too high, just tap them down a bit.
• Mix exactly the amount you need to get the desired thickness. If a particular SLC requires 1.7Kg powder per mm per m2, and you want to pour a 10mm layer on a surface which is 5m2, do 1.7kg x 10mm X 5m2. The result should be 85Kg. Make sure to mix in the exact amount of water stated in the specs though. Do a search for "materials calculator" on the forums, and you'll find a spreadsheet I made which you can use to calculate this.

There are other ways, but these are straight forward enough.

 

[Woody123]

Thanks for the info mate. Thats actually really useful.
Had a look at your materials calculator yesterday and saved it to me desktop. Looks like that could come in handy aswell!
Keep up the good work.

 

[sWe]

No problem mate. This is why I'm on these forums in the first place; to make what I know availible to others who want to listen, all whilst picking up tidbits of useful info myself

 

[Holohana]

is another option to put ply down perhaps or similar maybe? Depends on the difference your making up i know but just a thought. OK ill get me coat!

 

[Woody123]

Could end up being quite fiddly that like holohana but it's always good to hear different opinions!

 

[tfs]

Hey mate,

I would suggest you try your best yto remove as much of the adhesive from the substrate that you can (you may already have done this).

Not all screeds can bond sufficiently to substrates containg traces of adhesive although, there are some suitable for such conditions.

It would take you five minutes to call a manufacturer e.g. Ardex or F-Ball etc. (Ardex, would be most reccomended, both of these supply to both flooring and tiling industry) they will even call you back if nobody is free to take your call. Carborandrum rubbing blocks are ideal for old lino ahdhesive.

The adhesive you mentioned sounsda like one used about 20 to 30years back for stincking down linolium, I was talking to a collegue today abouth this but cant remember the name.

kris