Crumbly screed?

Dry biscuit screed - 8:1 w. sharp sand - laid 22 days ago. Leaving it to dry out for another 22/23 days on the basis of 1mm per day drying time. Then will lay 15mm engineered wood flooring across the battens embedded in the screed. I don't know what the texture of the screed should be like after this drying out period because right now it's crumbly and is not setting in the way, for example, a semi-dry 4:1+0.5 water based screed would. Am I right to worry that the screed will not harden; or am I just needlessly anxious? Some input on this subject from a more knowledgeable member would be really appreciated.

8-1 is probably to weak a mix T 22 days it’s going to be as hard as it will ever get 

2 hours ago, nod said:

8-1 is probably to weak a mix T 22 days it’s going to be as hard as it will ever get 

Everything I read said that 8:1 using sharp sand was the proportion to use. No deviation from that from anywhere

Sounds like your going to have to do it again

I've used 8:1 dry mix between my joists and after 2 weeks the humidity tells me it's dry. If you floated at the end it'll go solid but if you just screed it and leave it then it'll be crumbly. Either way was good for me as I'm just using it for mass, but by floating it meant it didn't just disintegrate while I was walking around it over the following few weeks. I learned this half way through my application of it.

Basically mine is like a cheesecake with a crust on top.