Which masonry construction do you recommend for the exterior walls?

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But I have been very skilled in craftsmanship for almost 20 years... I have already completed many many projects and, due to my profession, I am a millimeter fetishist... That's why I said that when laying the stones I PROBABLY put in more effort than a bricklayer who does nothing else all day... (...)

No bricklayer lays bricks crooked, and masonry really doesn't have to be accurate to the millimeter.

No bricklayer builds crooked

Then I have to send you my crew from Eberswalde...

Good morning,
We are currently building as well and putting a lot of our own work into our house.
Before building our own house, we helped a lot with friends/family and gained some experience. One of those experiences was gluing all the interior walls of a house with aerated concrete by ourselves. Our conclusion from that was that we would definitely not do the masonry ourselves for our house (Poroton). Sure, you can glue such a wall well yourself and with a string line and/or laser and spirit level, it will be wonderfully straight, but it simply takes incredibly long. I can agree with the estimate from that it takes 5 times as long. And that’s just the pure working time. For us, it was also the case that we couldn’t invest 8 or more hours every day. Preparing, mixing, cleaning up, cleaning tools, etc. also come into play even if you only glue for 4 hours.

At our own construction site, the situation now is that we pay a team of masons by the hour. They are very fast. Nevertheless, we still spend several hours every day on the construction site and do the work that you better do yourself and where you don’t get in the way of the masons. For example:
- Sealing the concrete basement (gluing fiber cement plugs)
- Gluing perimeter insulation
- Laying pipes in the ceiling (ventilation + electrical)
- Removing formwork + reconditioning formwork (takes a lot of time, can be done alongside other things anytime and you really don’t need to pay a mason for that)
- Laying drainage (pipes + flushing shafts) + fleece + Delta membrane
- Cleaning up and disposing of waste (sounds trivial, but you can save money here too)

For the wall construction, I would rely on what the masons do best.

Regarding the masonry, I would also say it doesn’t matter. I recently built a two-family house. A Thermoplan S8 Porotonstone in 36.5 cm was used. It meets the Building Energy Act and KFW 55. At the neighboring construction site, everything is done by themselves. The walls use the same stone. However, they also own or borrow machines. You definitely need a crane, a stone saw, scaffolding, props, and a bunch of other stuff. Doing it alone is always difficult, you should always be at least two people because otherwise you won’t get anywhere. What I mean is, you can certainly do your own foundation slab and build your walls, but you should maybe have someone with experience at hand and a helper who always has time (retiree or something similar) would be really important. The same applies to many things in the interior finishing.

Before building our own house, we helped friends/family a lot and gained some experience. One of those was gluing all the interior walls of a house with aerated concrete on our own. Our conclusion from that was that we definitely would not do the bricklaying ourselves in our house (Poroton). Sure, you can easily glue such a wall yourself and with a string and/or laser and spirit level it will be wonderfully straight, but it simply takes incredibly long. I can confirm @MachsSelbst’s estimate that it takes 5 times as long. And that is only the pure working time. For us, it was also the case that we could not invest 8 hours or more every day. However, preparing, mixing, cleaning up, cleaning tools, etc. also has to be done even if you only glue for 4 hours.

That sounds like you made the mistake of doing the shifts “after working hours” (i.e. already exhausted), otherwise even interior walls wouldn’t be so sluggish / tough. Indeed, interior walls (including those misused as exterior walls in ETICS) are more demanding insofar as they have less bearing surface relative to the layer height. And fundamentally ...

You definitely need a crane, a stone saw, scaffolding, props, and a bunch of other stuff. Doing it alone is always bad, you should always be at least two people, otherwise you won’t get anywhere.

When laying narrower and/or heavier walls, a second pair of hands of a person preferably the same size is one of the most important tools. Depending on the weight of the individual plan blocks, a crane is needed either only for placing the pallets (aerated concrete) or also additional lifting equipment or other positioning aids during the actual bricklaying (for heavy bricks, and in the narrow wall thicknesses possibly also for aerated concrete or gypsum boards). Many beginners / infrequent workers also underestimate their loss of performance with the increasing number of repetitions. After all, an aerated concrete block is also an ergonomically unfavorable model of a dumbbell. Special lifting tools help (to a limited extent). It is also tricky—even with the lightest brick—to work “overhead,” that is in layers seven or eight up to ten and a half / eleven. You usually no longer do this “ground-level,” but from the scaffolding or handed from below, that is already quite athletic. Watching it on the couch in a tutorial video beforehand is often underestimated. Together with the performance curve mentioned at the beginning, this quickly causes a considerable delay in the pace; the self-performed work therefore becomes increasingly difficult to schedule.