Tiling on a new screed floor? Is my tiler correct?

[upthecreek]

Hi there, I have read a lot about tiling on new screed and I'm still confused. Before I start with the questions I must state that I am not doing this job and I have got someone in but I am unsure that it's been done correctly. I have a 5 square meter utility room where the floor had to brought level with kitchen and then tiled throughout. Before this started, a trench was cut through the utility room (aprox 200mm x 200mm) in order to lay a soil pipe for the addition of a new cloakroom toilet. 2 days ago a sand/cement mixture was then pored to fill the trench and level the floor. Excluding the depth of the trench the screed was between ( 40mm-60mm). My tiler who was also the person who did the screed is telling me that he can tile in a week (he is using BAL stone and tile PTB). However there is conflicting advice surrounding thist. from a day for every mm to 1 week in total. I'm a typical customer and do not want to wait 60 days or more. I don't think he will be able to DITRA mat as this will bring the floor higher than the tiles in the kitchen (which he has already laid). Is BAL green cement adhesive the best option and how soon can this be applied after the screed has been laid. I wan't to get my facts right before he comes back in 5 days. I just want the job done right!

 

[Rookery]

I've not used it for a long time but I think BAL Green Screed adhesive can be used on a minimum 7 day old screed.

 

[Time's Ran Out]

Green screed adhesive can be used on sand/cement after 24 hours.
not sure about 'poured' sand/cement and the Ditra will only add 6mm which could be levelled to kitchen floor. Make sure you have an expansion joint between the 2 floors .

 

[upthecreek]

Thanks Rookery. Just done some further reading preparing and priming the screed for tiling and the removal of laitence from the screed surface. I have a suspision my tiler is going to just slap on PVA. I have read numerous horror stories of tiles lifting and cracking and the resulting discussions on who is to blame. What is the correct procedure? I'm starting to worry that I seem to know more than my tiler.

 

[Time's Ran Out]

Most customers also think that but really you should just ask him!

 

[upthecreek]

I will be asking but I just want to be asking the right questions. Have seen numerous threads where things have gone wrong and I want to avoid adding another. This seemed the best place to get a professional 2nd opinion.

 

[beanz]

It's a shame more customers don't ask these questions at the quote stage.. It might get rid of a bunch of these cowboys!

 

[Rookery]

Green screed adhesive can be used on sand/cement after 24 hours.
not sure about 'poured' sand/cement and the Ditra will only add 6mm which could be levelled to kitchen floor. Make sure you have an expansion joint between the 2 floors .

Yep, 24 hours for a sand/cement screed, 7 days for concrete.

 

[Dan]

Bumping this one too.