Hi Cristoph,
I'm sure someone with more experience than I will respond, but just to bump this a little I thought I would reply.
I hate the term "dry rot" because if it was dry, the fungus wouldn't be growing and rotting things. Getting rid of moisture is the number one way to discourage fungus, and it sounds like you have dealt with this. The treatment might be different if you are seeing this on the inside vs the outside of the wall. Perhaps once things dry, you could remove any soft
wood and spray with a natural anti-fungal just to be sure?
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