do i need to tank or will tiles be ok in my wetroom?

[DHTiling]

How old is the screed

 

[andypippa10]

The screed hasn't gone down yet as the rooms run level with a utility and kitchen, so just got to find kitchen tiles and will then all go down together. Just thought I could get the stuff I need ready so it can be done once the screed is dry and there seem to be lots on the market but wanted to make sure it was compatible with UFH and concrete as most wet floors seem to be upstairs on timbers.