Drying time of screed before leveling compound

For heated screed, the information provided by your installation company is correct; the readiness for covering for heated screeds is reached when, during the required CM measurement, screed moisture values of 1.8 CM % for cement screed and 0.3 CM % for calcium sulfate screed (anhydrite) are measured.

We have just gone through that as well. The drying time of the screed varies. There is a rule of thumb, but it does not have to be accurate. It depends on the weather and the local conditions. Also, which screed was used, that is also decisive.

My opinion is better to wait a little longer than to have major problems later.