Additional costs for residential units

Yes, Yvonne went too far there. But I didn't want to argue about it last night, especially since this topic with such exceptions is too complex, it would lead too far astray here.

Probably less. Overall, you also have to say that costs through TE should rather be saved, but or therefore everything should only be prepared. A tent roof is not optimal and suitable for that without factual knowledge (e.g. ceiling height, development plan, parking space). In the end, we are still talking about an attic, and yes, now I will also throw the suspicion of greed into the ring. Ultimately, the occupancy permit notice is also being swept under the rug.

I am not unfriendly, but rather have provided you with factual answers.

It is interesting that you see it that way. For my part, I am still waiting for answers (very gladly also "factual") to my open questions in order to form an opinion on whether my plans are feasible or not.

I will summarize for myself once again: conversion of an attic with a hip roof. The opinions/facts/problems gathered:
1.) Must be insulated. Apparently not a problem. At least I have not read anything to the effect that this would not be possible. To my question whether this is particularly difficult or expensive with a hip roof and whether an additional ceiling could/should be installed (in order not to have to insulate the apex), there has been no answer so far. Therefore, I currently assume that this is possible without extraordinary additional costs. If I am mistaken, enlighten me. Maybe with a rough estimate of what such insulation would cost more compared to the insulation of a regular ceiling with a cold roof above. Then one can get an idea whether this is acceptable or not.
2.) Must be lockable. No problem, this is ensured with a stairwell.
3.) A second escape route must be present. As far as I understand, this is relatively easy to implement if at least one skylight has a certain size and location. Both seem feasible for planning as far as I can see right now. I briefly googled and found various reports on how this can be implemented (e.g., "WSA R8 by Roto" as a keyword).

or Yvonne or whatever your name is: Sorry... but where exactly does your argument run that such a conversion will not work? You accuse me of being resistant to advice. Then please explain yourself more precisely, so I can also understand what exactly about the plan is not feasible or pointless. Meanwhile, quite a lot of what you have been saying does not sound factual. Your recent accusation of "greed" fits in well with that. It feels a bit like you switch directly to attack mode when not everyone accepts your opinion as an indisputable truth but asks further questions to understand and make an informed decision. For me, the question simply is: what do you want to achieve with this behavior? People with little experience come here and naturally ask "stupid" questions. Then you could answer them kindly and calmly and help them understand. Or can you blame them for sticking to their plans until it is properly demonstrated that they are not viable?

Then please explain yourself more precisely, then I can also understand what exactly about the plan is not feasible or pointless.

I never wrote or claimed that.

For my part, I am still waiting for answers (very gladly also "factual") to my open questions, in order to form an opinion about whether my plans are feasible or not.

The house building forum and also Yvonne are not Wikipedia.

so far there has been no answer.

Unanswered questions happen, you do not have the right to label a lack of answers as unfriendly. In principle, one can only say something definitive if facts are put on the table: location and development plan, size of the plot for price determination, etc. Your architect is the first contact for price assessments.

I will summarize for myself again: Conversion of an attic with a hip roof. The collected opinions/facts/problems: 1.) Must be insulated. Apparently no problem. At least I have not read anything suggesting that this would not be possible. In response to my question whether this is particularly difficult or expensive with a hip roof and whether an additional ceiling could/should be installed (to avoid insulating the peak), there has been no answer so far. Therefore, I currently assume that this is possible without extraordinary additional costs.

Even the hip roof itself will cost you significantly more compared to a gable roof - by the way, we do not know whether you intend to build it with rafters or trusses - than you could ever save with concentrated wet room stacks. Then also with an attic to save a handful of meters of insulation rolls, a Pyrrhic victory could hardly be bigger. You don’t build a decent house by squirrel-like gathering of parameters and aspects. Better start with planning instead of optimization.

To get back to the original question. If you only place the connections upwards (water, electricity, heating?), I don't think it will cost too much at first. I would rather ask how much more expensive the entire planning and also the shell construction (building envelope, parking spaces, etc.) will become because of this. Will the house be built higher so that there is still a knee wall on the upper floor? How far does the attic have to be built during construction in relation to [KfW40]? Insulation? Whether you install an insulated ceiling under the roof or insulate the entire roof up top probably won't make much difference in terms of costs. But without concrete planning of what the attic will look like, it's probably hard to say.

Unanswered questions happen, the law is not on your side to label missing answers as unfriendly.

Sorry, but at this level it simply makes no sense to talk to you. It was not the absence of answers that I labeled as unfriendly, but your derogatory judgment that I am resistant to advice. Please at least read the replies before denying anyone the right to anything.
In my opinion, it doesn’t make much sense with you: You have your opinion, but no arguments (or you don’t want to share them with me). Of course, I accept that. But based on that, I think neither of us benefits from the exchange.
If you still want to argue how you come to your position, feel free to do so, I’m happy to listen. Otherwise: Let it be.

Just the tent roof itself costs you compared to a gable roof

I know that. I read that you can plan with about 20% additional costs compared to a gable roof. That is worth it to me because I personally find the gable roof very unaesthetic and, in addition, with the otherwise simple design of the body ("square, practical, good") I would also like to set a more extravagant accent with the roof. Tent roofs with this pitch are rather rare around here.

By the way, we don’t know if you intend to build it with rafters or trusses

I can’t answer that yet because I don’t know the difference and the respective advantages and disadvantages. Thanks for the hint, I’ll try to read up on it (and if necessary ask stupid questions again).

considerably more than you could ever save with concentrated wet room risers

As I said before: It’s less about calculating against each other and saving enormously. I just wanted to ask for tips and tricks on how to contain the price when you have several residential units. I do not expect to get anything for free or even 3 for the price of 2 or something like that. I just want to plan sensibly and cost-efficiently where possible (or where it fits the aesthetic ideas).

You don’t build a proper house by squirrel-like collecting parameters and aspects. Better start with planning rather than optimization.

My floor plan planning is running in parallel. The questions asked here and your answers are still very important to me. Afterwards, an overall picture emerges for me from the interplay of all the information, tips, and hints. That might seem a bit erratic or incoherent to you now, but I am not only talking to you here but also with experienced friends, acquaintances, developers, architects, building authorities, and so on.
Therefore, all the information provided here certainly help me to better classify another building block. Maybe that’s too detail-obsessed, but I manage quite well with this kind of planning to approach a topic still largely unknown to me overall.

If you just place the connections upwards (water, electricity, heating?), it probably won’t cost too much at first, I think.

Thanks. That already reassures me.

I would rather ask how much more expensive the entire planning and also the shell construction (building envelope, parking spaces, etc.) will be because of that.

I’m still clarifying that. Especially with the parking spaces. For example, if more than three parking spaces are required for three residential units, that would seriously torpedo my plan.
It’s on me to ask that.

Will the house be built higher so that there is also a knee wall in the upper floor?

I have not planned that so far. The idea is as follows:
Ground floor and upper floor are complete stories. Then the tent roof with an expanded attic without an additional knee wall (this is the plan so far but can certainly still change).
According to my (of course amateur) calculations, this results in a ridge height of about 9.70 m. Up to 10.5 m should not be a problem on the property.

How far does the attic have to be built in relation to KFW40? Insulation?

That was basically one of my earlier questions. So: Is it anywhere specified what needs to be done to be eligible for subsidies for a residential unit with KfW40+? Are basically connections, insulation, and air filters (and other building standards) sufficient? Or does the thing have to be completely finished and do I have to open the door for the first tenant on the first day after completion?
Since especially the attic is to be completed by me myself in many places over the next years (tiles, installing sanitary facilities, etc.) before it goes to the child, it would be important for me to know what requirements the KfW imposes to approve a subsidy for a residential unit. So far, I have not found anything concrete from the official side. Has anyone had experience with this?

Whether you install an insulated ceiling under the roof again or insulate the entire roof to the top will probably not make much difference in terms of costs.

Okay, thanks. That is sufficient for me as a rough statement for now. Then I can plan with it first and I’m curious what my architect will say later.
Personally, I also imagine an upward open pitched roof in the attic very stylish. An additionally inserted ceiling was only an idea if it would provide a significant relief regarding insulation.