Poroton brick sought for sound requirements

In the development plan, the following applies to us: The required sound insulation measures of the external components must be demonstrated in the building regulation procedure depending on the type of room use and room sizes. However, this requirement may be deviated from in exceptional cases if it is proven in the building regulation procedure that in individual cases lower noise level areas are present at the facade. Does this probably mean that I need a calculation?

Yes, that is exactly what is written in there. So "actually" it has to be proven mathematically, and then unfortunately the conclusion is not so simple that a stone with a soundproofing value of 41dB meets the requirement of 40dB.

However, it also depends a bit on the building authority. In practice, I have experienced different approaches there (whether that is correct or not is another question). But I also know of building authorities that just want to see that you have taken care of it. In the end, they just want to get out of liability so that you can’t later claim that you have sleep disturbances, tinnitus, and delusions.

But I can already tell you that the calculation is a purely theoretical procedure. That does not necessarily mean that it will sound more or less quiet or loud to you afterward.

The question is, what is the noise based on? Is there a soundproofing report? Sometimes "hypothetical" situations are assumed there that in practice do not occur at all or at least very rarely.