Final energy demand achievable without insulation

much nicer than styrofoam on the facade.

You don't see a difference. You don't feel a difference. It's "just" a different construction method. Nothing more and nothing less. By the way, besides styrofoam and monolithic, there are plenty of other options.

Most people still build with unfilled bricks. Ytong is sound insulation worst case.

I cannot confirm that, the house is located close to a busy street and inside you actually hardly hear anything.

You don’t see a difference. You don’t feel a difference. It’s “just” a different construction method. Nothing more and nothing less. By the way, besides Styrofoam and monolithic, there are countless other options.

That’s true, you don’t see a difference, but you know it when you live inside, and from a fire safety perspective, Styrofoam discouraged me.

That's true, you can't see a difference, but you know it when you live in it, and from a fire protection perspective, Styrofoam put me off.

We also considered several times whether the extra cost for monolithic construction (hollow brick) compared to ETICS is worth it for us. There is an absolute war of beliefs on that. Ultimately, we were convinced by the statement that with proper execution ETICS is absolutely fine, but you can also do a lot wrong. When we paid more attention to it, we also saw quite a few houses that were cheerfully dotted. At the points where the insulation was doweled, the house wall dries faster, and over time there are color differences due to the weather. Well, fastenings like awnings are ultimately easier too.

These 17,x hardly have any significance for your consumption. In addition, it is the electricity specification.

I cannot confirm that, the house is close to a busy road and you can actually hear almost nothing inside.

Maybe you have a special type of stone? You can also check the datasheet for the regular Ytong, they are very poor.