Went to look at a job today, kitchen floor. Floor is concrete, very flat, good condition and will not need self-levelling. But where vinyl tiles have been taken up there is a small amount of old black adhesive remaining (could be bitumen? not sure?) but it is firm and hard and a very thin layer. Can I seal over this and tile? Or does it need to come up? If it needs to be removed what is the best way to do it? (i'd really like to just leave it!)
Would appreciate anyone's opinion on this. Thanks.

i called mapei technical today about said problem and the reccommend to remove it.

if its a big area you can hire a scabbler from hss, if its a small area you can get a grinding cup from any good tool shop or from @@@@@@@@.. google them!

as sir says below try Tradetiler they sponsor this forum you know!

Originally Posted by dagger

i called mapei technical today about said problem and the reccommend to remove it.

if its a big area you can hire a scabbler from hss, if its a small area you can get a grinding cup from any good tool shop or from Speedcrete.. google them!

Or Tradetiler

i dont think trade tiler sells what i mean but this is the kiddy:

So it definitely needs to come up? That's a shame. Area is approx 6m2.

(ps, off this subject, but I loved the wetroom diary Dagger! Great stuff!)

one of those diamond grinding cups will do that in no time at all,
but there is a downside..they are not cheap!

Originally Posted by dagger

one of those diamond grinding cups will do that in no time at all,
but there is a downside..they are not cheap!

Messy too I would imagine?
And I don't have a good angle grinder either! Just checked tradetiler and they do a Makita for just under £50, the grinding cup is approx £20, wire brush approx £5, so not too bad.
Anyone got the Makita angle grinder? Are they okay?

Originally Posted by Bartlett

Messy too I would imagine?
And I don't have a good angle grinder either! Just checked tradetiler and they do a Makita for just under £50, the grinding cup is approx £20, wire brush approx £5, so not too bad.
Anyone got the Makita angle grinder? Are they okay?

great prices, and i checked the cup out!
does not look as "quick" as the one i showed but for £20 you cant go wrong.

as for the mess you will cut it in 30cm2 sections and hover it up, its not too bad

Originally Posted by Bartlett

Messy too I would imagine?
And I don't have a good angle grinder either! Just checked tradetiler and they do a Makita for just under £50, the grinding cup is approx £20, wire brush approx £5, so not too bad.
Anyone got the Makita angle grinder? Are they okay?

They are great i have 3 ( 110v , 240v and one i have for general grinding)

You can Tile on top but you would need an epoxy primer, i know weber and PCI do one.

Originally Posted by TrumpersUnited

You can Tile on top but you would need an epoxy primer, i know weber and PCI do one.

Aha, that's interesting. I spoke to Mapei earlier to double-check and they confirmed that all bitumen should be removed 'as it can get warm and therefore become flexible.' So how does the epoxy primer deal with that?

If the old adhesive is well and truly stuck , then you can slurry coat over it...for increased adhesion.

Originally Posted by Dave

If the old adhesive is well and truly stuck , then you can slurry coat over it...for increased adhesion.

Sorry Dave, pardon my ignorance. I think I know what you mean but can you define 'slurry coat' for me?

Slurry coat is a mix of adhesive and water mixed thinly.

Slurry coat is portland cement mixed with SBR....or rapid set will suffice...but needs to be SBR...this helps with the adhesion of the slurry coat to difficult substrates...and tile on tile if needed.

Originally Posted by Dave

If the old adhesive is well and truly stuck , then you can slurry coat over it...for increased adhesion.

So despite the advice to the contrary from Mapei this really would be okay? ie, leave the adhesive in place (it is a very thin layer and seems firm) then slurry coat over it and then tile as normal? Sounds good to me.

Originally Posted by Bartlett

So despite the advice to the contrary from Mapei this really would be okay? ie, leave the adhesive in place (it is a very thin layer and seems firm) then slurry coat over it and then tile as normal? Sounds good to me.

Its worked for me for the last 32 years

Originally Posted by Sir Ramic

Its worked for me for the last 32 years

Haha, sounds good to me. So drawing on the benefit of your experience what mix should the slurry coat be? Or are we simply talking very thin and runny? Do you use cement or tile adhesive? I was planning to use Keraflex to do the floor tiling.

Originally Posted by Bartlett

So despite the advice to the contrary from Mapei this really would be okay? ie, leave the adhesive in place (it is a very thin layer and seems firm) then slurry coat over it and then tile as normal? Sounds good to me.

No disrespect to mapei, but they would have been advising you for only using tile adhesive and not using a slurry coat first.

Different method to just using adhesive over it....and yes it works well does a slurry coat.

Okay, final question (or maybe not?), just want to make sure I do this right!
Slurry coat and tile immediately after, or let it dry overnight?

If you were self levelling over it then i would say as soon as,but for adhesive then a few hrs is ok but don't leave it too long...

Sorry for delay, epoxy primers cause a barrier from the bituman to the adhesive, agree totally with Dave about a slurry coat another option is to use ditra or dural CI Matting

Having a same problem, told black adhesive is bitumen adhesive and may have
Asbestos mixed with it and bad idea to grind or sand or disturb in any way .

Old bitumen contained asbestos and was used as an adhesive for vinyl tiles many years ago, who no’s, contemporary bitumen might have different ingredients, but bitumen found its way in to many products, scary.

Never did tiling before, just having a go mate.
Gave the bitumen a good neat coat of Bal SBR Bond, still a bit tacky, also were no bitumen on concrete also still tacky almost two days later, almost dry.

If I was to give Floor Vinyl Tiles, Concrete, Old Bitumen adhesive left over from removing tiles,two coats of SBR neat will it take the floor Tiles better.
Thanks Mate.

Never did tiling before, just having a go mate.
Gave the bitumen a good neat coat of Bal SBR Bond, still a bit tacky, also were no bitumen on concrete also still tacky almost two days later, almost dry.
Hi
If I was to give Floor Vinyl Tiles, Concrete, Old Bitumen adhesive left over from removing tiles,two coats of SBR neat will it take the floor Tiles better.
Thanks Mate.