KFW 40+ One central ventilation system per residential unit?

I was just about to complain "we recently had this topic" and then had to realize: twenty minutes of hardcore forum search unfortunately is not enough to find the relevant twin post :-(

Unfortunately, I didn’t find anything about it either. But I was helped here.

Unfortunately, I haven’t found anything on that either. But here I was helped

The latter is positive for you, and it makes me happy too – nevertheless, it raises my concern that the forum is increasingly hard to navigate. If only you as a newbie can’t find something, that’s one thing, but if even I as a power user can’t find it – especially on a topic of which I am sure we have already discussed in almost the same question within the last three months – that’s another. Discussing a question "again" so closely borders, in my opinion, on double content (which I consider the noblest task of a forum search function to avoid). There is a difference whether the inevitable five percent of lazy searchers produce topic duplicates, or whether a majority is “forced” to do so because popular topics are not prominently findable. It’s not as if nothing is being done here for user comfort – just apparently not with a very lucky hand.

We only have a very small 1-room granny flat. We plan to exclude it from the central ventilation system and to realize it through a decentralized ventilation system. According to the architect, this makes the most sense.