Solid house or prefabricated house? Semi-detached house, approx. 160 sqm, pros and cons

I can only speak from my experience and from that I can confirm the aforementioned feeling. Objectively, this is certainly an apples-to-oranges comparison. Subjectively, however, it is perceptible.

That may be true, but it does not change the fact that here quoted a platitude that is repeatedly pushed around during every slow news period by Bäckerblume, Apotheken-Umschau, and Bildzeitung in turn: the myth of climatically pleasant and unpleasant houses as a comparison with the somehow wooden house as the winner. Without scientifically sound derivation, i.e., "generalized" without describing the experimental setup in more detail (even if only differentiating between with and without controlled residential ventilation, radiator and underfloor heating, clay or synthetic resin plasters, etc.). Simply following the motto: "whoever talks nonsense is sure to have the approval of the broad masses" :-(

I consider it a rumor that you only get floor plans from the catalog when dealing with a prefab house builder. Most gladly take your money and build your design, as long as it is physically possible. After over 2 years in this forum, I would put a big question mark behind whether it is a good idea for the builder to just show up with their design and expect only it to be implemented. Floor plans are a complex topic, but you can find help in the corresponding subforum.

For special wishes regarding the type of construction or certain self-performed work, it might also make sense to consider building with an architect and individual contracts instead of a general contractor (whether solid or prefab). Removing trades one after another from a general contractor is not necessarily the most cost-effective way to build. And if, for example, you do the electrical work yourself, a prefab house really only makes sense with an installation level.

In the meantime, we have been to several prefab house builders and almost always they laid a catalog in front of us and adjusted an existing house so that it comes close to our plans. Our plans, by the way, come from the architect. Fundamentally, we do not insist on this floor plan... if there are suggestions for improvement (nobody is infallible) or if we have overlooked something, highly welcome.

The construction execution is a topic. We have a lot in the family and many capable hands, but I believe it is simply too complex for an office type to manage coordination and individual contracts sensibly. Simply put: I don’t really trust ourselves with it and we respect all the work involved... we both work full time with kids :/ Therefore, more towards the direction that someone takes it into their own hands.

Individual contracting does not mean that you as the client also play the role of the site manager. You leave that to a professional. But the point is this: with a general contractor (GU), you have a contract with the GU as well as a construction description. You do not have a contract with the individual craftsmen; everything goes through the GU. If you want to change something, you do it according to the GU’s price expectations. If the GU thinks that you only get credited €5000 for doing it yourself... your problem. In contrast, with individual contracting, there is a tender (prepared with the architect), and you as the client sign contracts directly with the craftsmen. You pay exactly what the tradesperson wants for each trade, and you can specify exactly what you want. If your cousin-in-law takes on a trade, this is much easier to do.

We are building with a GU, but I would do the next house with individual contracting. The main reason is communication, because my GU is not good at it. Since everything goes through the GU, I have to constantly chase after all information. Also, with individual contracting, you see the individual prices and can better consider whether certain things are worth the money. Next time I also want a site manager who only represents my interests and does not overlook poorly executed masonry work and horizontal chases.

We are building with a general contractor, but the next house I would do with individual contracts. The main reason is the issue of communication, because my general contractor is not good at it. Since everything goes through the general contractor, I constantly have to chase after all the information. Also, with individual contracts you can see the individual prices and can better consider whether certain things are worth the money. Next time I also want a site manager who only represents my interests and does not overlook poorly executed masonry work and horizontal chases.

Full agreement! Exactly my experience!

We have now been to several prefabricated house builders and almost always they handed us the catalog and adjusted an existing house so that it comes close to our plans. By the way, our plans come from the architect. Basically, however, we do not insist on this floor plan... if there are suggestions for improvement (no one is infallible) or if we have overlooked something, highly welcome.

I have already suggested that you show the design once. The seal of quality "self-paid architect" alone guarantees nothing; this forum community usually finds suggestions for improvement (which you do not have to accept all). Many brick construction general contractors do not have their own catalogs at all and therefore like to build "individually," which also has disadvantages. The "prefab" house manufacturers are often large and correspondingly set up industrially in all processes, but unfortunately are gradually moving away from well-composed typical house portfolios. For the semi-detached house, I like to recommend asking BT instead of GU - the house type is more their domain.

On the other hand, with individual contracting, you have a tender (created with the architect) and you as the client conclude contracts directly with the craftsmen. [...] In addition, with individual contracting, you can see the individual prices and can better decide whether certain things are worth the money.

This is an important correlation: the success of the awarding strictly depends essentially on the quality of the tender. However, I would never conclude that Mercedes offers poor price-performance with the horn simply because it is more expensive individually than on the Opel, even though it is an identically trivial component. Both vehicles were acquired as complete systems at a total price. Although I am otherwise not a fan of the balanced scorecard, in construction with a general contractor this concept has its advantages.