Is a house connection room under the house useful?

Is there even a MUST standard over there? The huts there are made of wood, we use concrete, including the floor.

The individual states have very extensive legislative powers. I would be very surprised if there were uniformly prescribed standards that applied to the entire USA. In the late 80s, you could build largely as you wanted in rural New Mexico but not wherever you wanted. In Santa Fe, there were many regulations because the cityscape was to be preserved. The Governor's building from 1610 is, by the way, the oldest public building in the country. Not everything in the “new world” is that new.

I regularly watch fixer upper on sixx. You can see how the Americans build there. Yes, you can't generalize, but sometimes it's frighteningly simple. No moisture barrier, no insulation, nothing, just beams and battens. Of course, it won't be like that in the colder north, but there's a reason every second hurricane blows the houses away.

Houses are not as emotionally charged everywhere as they are with us. People move when it no longer fits the stage of life, like they exchange a car. The claim to permanence and capital accumulation for the descendants is largely foreign. From this also follow different houses. They are utilitarian objects - sometimes only designed for 15 years. Energy and air conditioning are cheap, so a high insulation standard is not worthwhile. Our training and master craftsman system in the trades is at a qualitatively comparable level in very few countries. There are many reasons. It's not worse because of this - just different.

Also, you shouldn't forget a few things: 1) Wood is cheap in large parts of the USA. Like, really cheap. And you can do a lot yourself. That's no comparison of the costs between wood and stone. 2) A full-grown hurricane also tears apart quite a few houses here. A wooden house is cheaper and faster to rebuild then. 3) As hampshire says, the relationship to the house is different. 4) There are many areas in the USA that are not climatically comparable to us. 5) The USA mostly has truly poor soil because it was hardly compacted during the ice age. That's why almost everything has to be founded on piles there. Here, you can usually build on slabs, which is much simpler. If you were to create an "installation level," you would first need a support grid on which the slab rests. Possibly even in the basement, which would cause even more soil excavation. Or the house would stick further out of the ground, which then presents another frost protection problem. Ultimately, you could do it, but whether the benefit is in a reasonable proportion to the additional cost is another question.

Is there even a MUST standard over there? The cabins there are made of wood, we use concrete, including the floor.

There are standards in the USA as well, for example the "model codes" of the "American Society of Civil Engineers" (ASCE) – similar to our DIN standards. However, which areas are regulated there and to what extent these are mandatory for private individuals is another question.