Are construction costs transferable to small houses?

It would definitely be interesting to get input / advice regarding air-to-water heat pumps and noise level.

Completely preventing the noises will not work. The Vaillant air heat pumps are already quite quiet. Ours, at least, is "barely" audible up to the street.
It's about 6 meters away. The tower inside hums a bit more under load. But if I close the door to the utility room, I no longer hear it in the living/dining area. Our bedroom is at the other end of the house, so it's quiet there.
However, you should calmly listen to the noise under "load". Because they are not quite as quiet as a gas boiler. ;)

completely preventing the noises will not work. The Vaillant air heat pumps are already quite quiet. Ours, at least, is "barely" audible up to the street. It's about 6 meters. The tower inside hums a bit more under load. But if I close the door to the utility room, I no longer hear it in the living/dining area. Our bedroom is at the other end of the house, so it's quiet there. However, one should calmly listen to the noises under "load." Because they are not quite as quiet as a gas boiler. ;)

In the floor plan proposal, the utility room was placed next to the bedroom; I would have changed that so that the bathroom is in between. I wonder where one can listen to such a thing under load. There probably won't be any heat pumps at the sampling center. I'll ask if any of their show homes have them. Whether they then operate under load is of course the question. Thanks for the tips

Oh, regarding indoor noise: In a 50 sqm house, the distance is of course short even if there is a small bathroom in between.

I also don't pay exactly little (per sqm), almost 200K for the house and as I said, 30K or worst case 60K or more additional costs, so in the end you naturally don't want noise pollution in your own four walls. Refrigerators actually annoy me already because of the noise (-;

Let's see what comes out of the next conversation, unfortunately I can't just sign anything spontaneously, you work 20 years for that.

If necessary, I would have to see if it can be built for less money by myself. Whether you end up with similar quality and insulation as when a company manufactures it in the factory is questionable. With a delivery time of 1.5 years currently, you might even get it faster, although at the moment you probably get few offers.

I wonder where you can listen to something like this under load.

I easily listened to it at another homeowner's place, who has a house from the same company as I do. I didn't go into a model home, but listened to it under real conditions.
Certainly, it is better if there is at least one room, if not two rooms, in between... as already mentioned, the inner tower buzzes louder in my ears than the outer part. The outer part just makes a slight noise.

In the floor plan proposal, the utility room was placed next to the bedroom, I would have changed that so that the bathroom is in between.

I wonder where one can listen to something like that under load. There probably won’t be heat pumps at the sampling center. I’ll ask if any of their show houses have one. Whether it runs under load is, of course, the question.

Thanks for the tips

We have the bedroom next to the utility room. There is a wardrobe against the wall, but the bedroom door adjoins the door to the utility room. And although the doors are often open (at least the bedroom door because of the cat), you don’t hear the indoor unit in the bedroom, not even a little. You can hear the indoor unit in the utility room itself, but much quieter than a refrigerator (at least ours is louder). You can’t hear the outdoor unit inside at all. Not even in the utility room, where it stands directly outside. What we find much more disturbing is that the outdoor unit constantly produces an airflow that is directed exactly onto our yard, where I get out of the car or often have to pass by. THAT is a reason for us to possibly reconsider a different location for the unit. The annoying thing is, the general contractor advised us not to put the unit next to the bedroom. But it wouldn’t have been disturbing there at all.

But if you want to hear one under load, just walk through new housing developments and, if necessary, ask people if you can listen.

Interesting input / advice regarding air-to-water heat pumps and noise level would definitely be interesting.

Should I ever become Chancellor of Germany, new approvals for such buzzing boxes will only be granted directly next to the operator's pillow. I am amazed on every dog walk how the frequency range was managed in such a way that it bothers humans more than the dog. Furthermore, EVERY cheap fan gradually becomes "louder" over time.