ᐅ Street Noise in Penthouse Apartment / Attic Flat

Hello everyone,
we are looking at a very spacious penthouse apartment on the third floor of a multi-family building, which we can almost completely customize thanks to the early stage of the project. However, we have a concern where we hope to rely on your extensive experience: The building is located directly on a busy village street. The architect doesn’t see this as a problem, for the following reasons:

• As part of the renovation of the nearby village square, the street will be resurfaced with a noise-reducing pavement. This should absorb most of the tire noise.
• The street will be downgraded from a cantonal road to a local road and converted into a 30 km/h (about 20 mph) zone.
• He further argues based on the sound cone. Since the building is so close to the street, the sound from the cars goes straight upward. We practically only hear something if we lean over the railing.

In theory, these are all good points. But does anyone have concrete experience with such a situation? We are worried that when we dine or relax on this spacious terrace, we will constantly be surrounded by street noise. Of course, you will hear a motorcycle now and then, but what about regular street traffic?

Thank you very much for your help! Regards, Stefan