Solid house: Which stone / brick?

The most important thing first:

I consider the discussion to be completely overrated.

That's how it is. The moon doesn't care whether a single builder cries to it or whether forum members engage in a singer dispute. Nevertheless, I would like to

I responded to 11ant's physical principle, which is simply wrong.

not leave this unchallenged, because there was nothing wrong: I pointed out that 1. mineral wool is a tangle, i.e. it consists of interwoven fibers, and the stiffness moment of this mutual spatial interlocking is more than adequate to counteract the gravity of the individual fiber, consequently the fatigue of the structure of the individual fiber only has a weak effect; 2. each individual chamber of such a hollow block stone in cross-section is very tall and narrow, i.e. it has a long-stroke cross-section, meaning the spring made of tangle-structure permeated with spaces can scarcely react to compression from its own weight by escaping sideways. Furthermore, 3. the still possible slight settling is limited by the fact that every quarter meter a bearing joint locks the fall – the latter also applies to bulk material.

Mineral wool settles when wet.

That is correct, but in mat form inserted as "air layers" between masonry shells it has a significantly more dramatic effect than in hollow block stone chambers, which are also much less frequently affected by possible water ingress. In an "air layer" this problem is more frequent, while in a hollow block stone chamber a crack or a joint would have to conduct water, i.e. after a pipe break this phenomenon is to be expected.

Fill materials generally settle much more strongly, because over the long term "continuous" thermal work and small vibrations lead to a Tetris-like breakdown of intermediate spaces. Note well that this applies b) here again only within one course of stones and a) brings us back to the beginning of the post
The most important thing first:

I consider the discussion to be completely overrated.

whose core insight is that the world will not end because of it. If the described phenomena in stone fillings gained dramatic relevance, you would already have to see noticeable layering lines on the top edge of every stone course in thermographies of such houses after 20 years – Could it really be solely due to my limited world knowledge that such images are not known to me? – surely some doomsday dramatist would have broadcast this on YouTube by now.

Honestly: the tendency of the builder generation "enlightened consumers" toward prenatal diagnostics of their dream houses has, in my opinion, reached pathological dimensions. The saying that the devil is in the details is often taken far too literally and turned into a general suspicion toward every detail.

@11ant do you mean mineral wool or also the perlite bricks with cream layers? Why do you not think much of them?

In general, regarding the topic "filling hollow block stone chambers," I have the feeling that product developers got ideas looking at lemon rolls in bakery displays, which one would actually rather have attributed to hash cookies. I'm still waiting for someone to fill Aloe Vera gel instead of fibers, granules, or mortar-like creams into the hollow block stone chambers. Promotional weeks at Baustoff Meier: Poroton with wild garlic, or something like that. People used to go to the basement to laugh without first asking if it was made from waterproof concrete, if you know what I mean...

I cannot – mind you, with all respect to the "once-in-a-lifetime" feeling! – laugh enough at how some people make a many-voiced outcry about every single detail in all facets, while right next to them happy builders put up a simple "House from Nikolaus 113" without rainshower and even with a doorway kitchen. People google too much for minor crap and too little for Pareto.

By the way, I live happily in pumice and have never written to my landlord asking if he is gluten-free.

I am currently considering using insulated bricks with mineral wool, but afraid of mold formation. Do you have an opinion on this?

Yep...that's nonsense.

I am currently considering using insulated bricks with mineral wool, but I am afraid of mold formation. Do you have an opinion on that?

You don't need to be afraid. Where should it come from?

Have you ever cut through a wall and proven the opposite? Did I claim that mineral wool collapses in masonry? No, I did not. I responded to 11ant's physical principle, which is simply wrong.

Mineral wool collapses when wet. You can read this in every processing instruction of such a product. Whether such damage regularly occurs in masonry, we cannot know here. But the physical property is there, unlike perlite, so 11ant's statement is wrong.

Of course mineral wool collapses when it gets wet, but only if it is permanently wet/is wet continuously. And how often does something like that happen in masonry?

Honestly, I believe that you have never held a Unipor brick in your hands. Friends of ours built with this brick, and together with my buddy we experimented with 2-3 of these bricks before the construction phase, since he also had this fear. Even with continuous sprinkling from a handheld shower over several hours, no real collapse of the filling could be detected. Both he and I then built with this brick.

During the construction phase, our construction companies, we had different ones, paid meticulous attention to ensuring that the wall crowns were properly covered.

People Google too much about petty crap and too little about Pareto.

Thank you for your detailed response. Although I think that searching the internet for information about the type of stone with which he is building his house, which a) costs a lot of money and b) should last as long as promised, has nothing to do with petty crap.

What are your Pareto points?

@ which stone exactly? UNIPOR or?

to use insulated bricks with mineral wool, but fear of mold growth

Yep... that's nonsense.

Let’s nevertheless spread this nonsense wide, i.e. take the fear once seriously as a working hypothesis: so what happens in the worst case?
Our assumption is then, yes, mold forms in the cavities. What would it most likely colonize? – the fibers of the mineral wool. There isn’t much airflow in the cavities, so the fungal spores settle (in our assumption, mind you!) along the fibers up to the cavity walls, which they ultimately line. Can they then draw nourishment from the mortar joints? – rather no. Can they migrate further from there into the plaster? – also hardly: on the one hand for chemical reasons, on the other hand the osmotic pressure is probably too weak here. So remaining – mind you, under the assumption of the "infested" cavity – is the possibility that the latter is drilled into, and that spread is possible through the hole. But this will not lead to relevant indoor air contamination. That’s my long form explanation – so you see: yes, it’s nonsense, this was the "calculation path" for that.

that searching on the internet for information about the type of stone he is building his house with, which a) costs a lot of money and b) should ideally last as promised for a long time, has nothing to do with nitpicking

The searching for information itself is certainly acting responsibly. However, I recommend keeping the depth of investigation into the range of offers – which neither include the extremes “Messiah” nor “Lucifer” and often not even the vice-extremes “the egg of Columbus” or “plague” – at an appropriate level. Furthermore, I have my doubts about the hope that Excel spreadsheets would be a suitable enzyme to digest all the parameters of data sheets from the vastness of the internet. Without willingness to accept residual risk, building is only possible in theory. And even if the world is bad: not every building material manufacturer can be a charlatan. However, some builders apparently live in the constant fear that some building materials are like a kind of magic ink, and their beautiful house would suddenly become invisible shortly after paying it off, just because they took “the wrong stone” (which in my opinion exists no more than the philosopher’s stone). And every building material has its advantages and disadvantages; the Wolpertinger building material factories have not yet been founded – presumably due to a lack of Daniel Düsentrieb (Gyro Gearloose) in the skilled labor market.

What are your Pareto points?

I do not understand the question, but I infer ignorance of the mentioned person: the Italian economist Vilfredo Pareto formulated a theorem according to which the steepness of an effort-benefit ratio beyond eighty-percent target achievement increases so strongly that the dissatisfaction of those who nevertheless continue to make an effort could be “topped” only by Sisyphus. And that’s what I mean by “nitpicking”: not the stone itself, but the further search for an even better building material when you have already found one that is more than sufficiently good – the further possible “gain” is then no longer worth the life time wasted on “information” searching.