Cracked screed over underfloor heating

[jazz-uk]

Hi

Had an extension built and as part of that had hot water underfloor heating under an anhydride screed floor. The floor went down over six months ago, but for various reasons has only been switched on properly today.

A few hours after it was switched on a couple of cracks have appeared in the screed. The screed is approx 50mm deep and a underfloor technician said it would be okay on normal temperature as the screed would be 100% dry.

Are these cracks okay or are they part of a bigger problem?
What do I need to do now?
My intentions are to tile part of the area and put laminate on the rest.

Thanks

 

[Robert too]

is the 50mm screed depth the cover on the pipes or total depth ,

and was any mesh reinforcemnt placed in the screed