ᐅ Mold on grout due to condensation?

Hello,

Is this mold concerning, or is it normal due to condensation?

Condensation usually forms on the coldest part of the room, which is the window pane. I believe the water then runs down into the joint and causes mold there.

Is this correct, or should I be worried?

I have attached photos....

Hello,

Fränky schrieb:
...is this mold a concern or is it normal because of condensation.

It is a concern; mold is not normal.

Fränky schrieb:
... I think the water then runs down into the joint and molds there.

That is correct, but how does the water run "uphill"? See Picture 1, left corner!
The reveals, lintels, and knee walls of the dormer in the roof covering are thermal bridges and require careful workmanship (insulation according to DIN 4108). If this is neglected, it leads to the problems described here.

Best regards.

Yesterday, I removed the old sealant and checked underneath. There was nothing to see, so it was just surface mold. I’m relieved for now...

I renewed the sealant and cleaned everything with a chlorine-based cleaner.

From now on, I will always dry wipe after showering and ventilate even more.

Nothing should happen again then.