Basement as a white tank - heating?!

Is a bit off topic, but why not just omit the basement? Plan the floor plan with storage rooms and a basement is not necessary at all. Saves a whole lot of money besides.

It's a bit off topic, but why not simply leave out the basement? Plan the floor plan with storage rooms and then a basement isn't necessary at all. It also saves a lot of money.

We are limited by the building envelope if we want a covered terrace (that's what the development plan specifies). Then we can only build 11 meters deep. In terms of width, we're limited to 7-8 meters (depending on the garage). If we don't want totally awkward rooms in the semi-detached house, almost the only option left is a basement. After all, we have to accommodate 3 children.

We have absolutely no problems with our white tank, on the contrary, we are super satisfied. We have underfloor heating in all rooms except the technical room, storage, and laundry room, but we have a controlled residential ventilation system. In hindsight, I wish I had installed underfloor heating in the basement as well, I would find it more comfortable. If the basement is supposed to be living space (playroom or something like that), then definitely heating, otherwise you will regret it... And for such a room, take a larger basement window, I saw that at the neighbor's and wouldn't have thought it makes such a big difference!

Don't get me wrong, we don't have any problems with moisture in the basement. But especially in summer, the dehumidifier from @Bockstars must be simple for a reason, otherwise you’ll bring in more moisture than you get rid of.

That you want to equate the basement with the ground floor room climate, you can forget about that with WU or masonry basement. Just for comparison, in the ground floor I had 35% in February and in the basement 55-60%, and those are really good values for a basement in the first year.

Is it possible to connect the basement to the [Kontrollierte-Wohnraumlüftung] device without heating it?

So a utility basement outside the thermal envelope, with central ventilation?
Theoretically, you would then have to bypass the heat recovery.

That way, you would save the operation of the dehumidifier and still have fresh air.
However, with a [Kontrollierte-Wohnraumlüftung] bypassing the heat recovery, you would probably need two different circuits because living and basement spaces have different requirements regarding the dew point.

An alternative might be decentralized ventilation systems that can be controlled based on the dew point, right? Two of them installed in the basement.
But that would mix central and decentralized again.

Or is it all nonsense?

You will not be able to do without the dehumidifier in any version. With/without underfloor heating and/or [Kontrollierte-Wohnraumlüftung] does not matter. The dehumidifier will be mandatory. Often in summer. Occasionally in winter.