Substrate query

[rj1884]

Hi all, I've been sent through this photo from a job I'm going to look at next week. I've been told that the flooring in the photo which used to have carpet on it is concrete. Before I go and look has anyone seen a substrate like this before. also what could the black on the floor be, could it be something that was either used to stick the carpet down or based on the square shapes on the floor could it be from old tiles that may have been down years ago. Thanks in advance

 

[Ian]

Looks like bitumen from Marley tiles.

 

[Qwerty]

Looks like bitumen from Marley tiles.

Yes, exactly that from the looks of it. Scrape up as much as possible, then consider a applying a slurry coat of SPF with SBR (numerous posts on here about it). I've been dealing with it this way for years and have never had any issues.

 

[DHTiling]

As above for me ^^^^^^ or you can prime with mapei eco-prim grip.

 

[rj1884]

Thank you for your replies, much appreciated. Could I also over lay it with either ditra or hardier backer or is it as easy just to self smooth and then tile. If self smoothing which would be the best one to use.

 

[Dougs Third Go]

have old vinyl tiles been down?, if so I'd get a het gun on there to remove as much of the addy as possible, then a cement/sbr slurry coat. I wouldn't bother with a ditra or hardie (not recommended over concrete anyway) then use an slc.The one I use these days is Tilemaster level flex.

 

[rj1884]

She's not sure, she just had carpet down. I'm guessing that at some stage vinyl tiles would have been down.