Tiling on screed with UFH, tiles and wood floor

[masamune]

I have a 20 sqrm extended space with wet UFH that will be tiled with large 80x80 tiles. An additive mix was used to accelerate the curing to two weeks. The humidity readings are now 2.5% and the screed company said it is ready for tiling. The manifold has not been fitted yet and screed is not test heated.

I have concerns as the builder initially said they would heat up the floor and let cool down for tiling, which I read in the BAL website as the standard process?

Now it seems that a few things have not been timed correctly and we may run out of time for a kitchen delivery, so tiling could start without heating up the system beforehand?!

I also insisted on decoupling membrane to be used (will post more info later) rather than just adhesive, so the contractor tiling will use BAL flex adhesive with Durabase CI matting. My understanding is that it is a standard for the screed to be gradually heated and tested before tiling.

I will post more later on the transition from the tiled floor to the existing suspended wooden floor.

 

[masamune]

I rang the screed manufacturer and they said "I seriously doubt you will get a tiler to lay down tiles on a UFH screed that has not been fully commissioned".

I confronted my builders with this info and they argued they have done many jobs without commissioning ufh before tiling!
"Because we have decoupling mat it shouldn't be an issue..."

Aren't we supposed to test the screed??

Obviously I'd rather go with the screed tech support advice and not risk it.

The next thing is that I have suspended floors in the old house with wood on top. Where the tiles meet the wood floor at an opening of 2m we will insert the matt underneath. My question is both technical and aesthetic. I want to put a nice metal strip flush between the wood and tile. What sort of preparation would be good on either side of the strip and any tolerances to allow for expansion?

The other room will be tiles everywhere going from the kitchen to the utility room. The utility is old suspended floor underneath and ply on top. It will all be laid with the duramat. Any concerns in terms of prepararion?