Too much moisture in the single-family house after screed installation? Risk of mold?

By the time the screed comes in for me, it will rather be summer, so I hadn't really given it much thought yet. Up until now, I had kept it calm in my mind, but I found it crazy how quickly mold appears there and definitely want to avoid that. But then I'll wait until the screed becomes more concrete before planning more.

We are building with 2 full floors and an unheated attic above. So there are no skylights, but in the attic we will definitely tilt the windows if moisture comes in through the hatch.

Make sure to close the hatch to the attic! Moist air collects there and attacks the roof beams.

Does anyone here know about mold? How is this usually removed? Sanding + chemical treatment and done? Does it possibly come back after a few months since the mold presumably still remains in the wooden beam? How do you deal with something like this?

First, relax. Mold comes and can also go. It is not INSIDE the wood like a woodworm. It is always important to eliminate the causes and not (just) the black spots. As soon as a balanced temperature/humidity ratio is established, mold should no longer be a problem. Above all, regularly air out the moist air and do not skimp on room temperature.

This certainly happens more often nowadays...

Sure, everything has to go fast nowadays. A house is built within weeks today. Wood is only moderately well dried, moisture is blown out of the house as quickly as possible with an incredible amount of energy. You just have to look at how many hundreds of liters of water are in wall plaster or floors. Most of that has to go back out of the rooms. Preferably sooner rather than later. Such unwanted consequences are thus inevitable.