Timber frame construction, which company is good

what I rather meant was that some prefabricated house manufacturers nowadays also use ecological and sustainable insulation materials. Many, on the other hand, still put Styrofoam on the outside [...] I don’t know what has changed in the last 2 years.

The eco-bio wave already caught on with prefabricated house builders twenty years ago. Back then, it was even possible to choose a different insulation material of the same thickness. Today, it would first have to be recalculated whether the desired U-value is still achieved. That’s why wall thicknesses in "eco" construction today can differ by 2 cm. The change in the last two years is that the Energy Saving Ordinance 2016 replaced the Energy Saving Ordinance 2014.

However, there are also various wars of belief about this.

These are nowadays more a consequence of this "insulation craze" and then affect "both" construction methods (timber frame prefabricated panels and masonry). There was no beating around the bush about "eco," it was requested and offered - done. Back then, insulation was only inside (in prefabricated timber frame construction, in solid construction between masonry shells). Bonding insulation panels of, to put it mildly, petrochemical provenance is a very recent (mis)development. The discussion about insulation, over-insulation, and over-over-insulation is also a bona fide war of beliefs: facts exist - on all sides - but in the minority.

For me, the advantages of a local carpentry shop prevailed. For others, it surely looks different. Everyone has to weigh that up.

That’s where the advantage of a local carpentry comes into play: with its "small series production," it can perfectly follow the customer's wish to individually design their wall structure.

I also don’t know which prefab house providers offer installation levels.

I don’t know that either - what do you mean by that anyway: does your provider install empty conduit systems?

My experience: the big providers are interesting if you stick to the standard houses they offer. If the room concept, size, and everything else fits, you get a house for a good price. But if you want to change something here, the costs go up immensely. Everything outside the standard is expensive.

And then the smaller, local provider becomes interesting. I also agree with 11ant here, not without a good architect, but you can certainly implement a custom-designed house with a local company. Advantage: all other trades are usually local craftsmen and also still "accessible" after the construction phase. In my experience, heating systems ALWAYS and EXCLUSIVELY cause trouble on Friday evening, and if you have a heating engineer in the village who is ready to come immediately, you will come to greatly appreciate the advantages of local providers.

But according to the companies mentioned here by the OP, it seems more like a general contractor with a standard program is sought, right?

I don't know that either - what do you even mean by that: does your provider install empty conduit systems?

The installation layer is only attached to the wall after the house shell is completed. "Wooden slats" where the installations are then made in between, the rest is insulated and covered. So that the airtight layer is not penetrated (outside for outdoor lighting, sockets, etc.), since it comes after the installation layer. Empty conduits or cables are installed as own work.

Everything outside the standard becomes expensive.

And then the smaller, local provider becomes interesting. I agree with 11ant here, not without a good architect, but the implementation of a custom-designed house can certainly also be done with a local company. Advantage: all other trades are usually local craftsmen as well and still "accessible" even after the construction phase. [...]

But according to the companies mentioned here by the OP, a general contractor with a standard program is probably being sought, right?

"Standard" in the sense of "model homes" basically no longer exists (unfortunately) – routines also provide security.

My reference to architectural planning was specifically aimed at the small carpenter who has little experience as a house provider. The "big ones" are all experienced here and can now also think well beyond their five-and-a-half-meter grid.

And they are typically genuine full-service providers, now mostly with their own basement construction subsidiaries. The carpenter is more of a consortium leader with subcontractors for all the other trades – which he probably masters all the better the closer you build to his company headquarters.

Can you also provide facts for your outrageous claims?

inzwischen mehrheitlich mit eigenen Kellerbau-Töchtern

I absolutely deny something like that, as well as many other things you spout here.

"Standard" in the sense of "typical houses" practically no longer exists (unfortunately) - routines also provide security.

My experience is completely different. I name two other companies here: Baufritz and Sonnleitner. Both offer fixed house types; if you choose one of these and stick to the standard, the price/performance ratio is really good. Any small change ("could the house be built 60cm wider?") costs disproportionately much. Custom-designed houses were exorbitantly more expensive.

At first (also because you can find much more about these companies online, for example) we were also looking at the usual general contractors, checked out their typical houses, and thought: oh yes, this one roughly fits in size, a little more here, a little less there, but basically. Oh, and all this for under €300,000, how wonderful! But exactly that "a little more here, a little less there" deviates from the standard and then a price under €300,000 was immediately obsolete.