Water is dripping from the concrete ceiling - What is the cause?

Hello everyone,

I have a question. We are now in the building phase. The shell, the roof + windows are in. The rough heating installation starts next week.

Now to my problem. In the living room, it has been dripping minimally from the ceiling for about 1 month. But only at this one spot. I am attaching photos. I have already searched everything. The upper floor is dry, the attic is dry. Everywhere else in the house is dry, even though it has rained heavily in the last few days.

The bricklayer doesn't know where it could be coming from.

What kind of floor is installed above the living room ceiling or has some sort of floor structure already been made there? Basically, water can also come from somewhere else - water finds its way... It can also become wetter during the current heavy rain in a shell construction than if the drainage is already attached and the facade plastered. Construction moisture is probably to be excluded?

Exterior plaster on it? Windowsills included if not I would still be quite relaxed about it.

There is no construction above yet. The floor; precast slab and then poured with concrete. Construction moisture is to be excluded.

No, the exterior plaster is not on yet. The exterior window sills were installed on Saturday. Interior window sills have been ordered.

So I can only speak from my own experience. As soon as the roof was on, without windows and plaster, nothing dripped anymore. Before that, it ran down the chimney and the stairwell!

But it doesn’t really look very wet either. Maybe it’s coming from the drying of the concrete ceiling?

yes, I hope so. As I said, otherwise the construction is completely dry everywhere.