Controlled residential ventilation system - maximum duct lengths - consequences?

In retrospect, the last post probably doesn't help you much either.

What I meant to say: You have to live with some lazy compromises, but you should be careful not to accumulate too many of them overall. For you, that means: Improve where it is possible without unreasonably high effort.

If it has to be flat duct, okay. But if I were you, I would check whether I can install the distributor(s) more centrally. However, that naturally requires a thicker (180mm) pipe between the controlled residential ventilation system and the distributor (still space somewhere for a riser shaft, or a suspended ceiling?)

Recalculate the airflow volumes, and if they stay the same, consider a different manufacturer with larger units.

And in general: The valves don't necessarily have to be placed in the back corner of the room or obligatorily on the ceiling. This is a requirement that many apparently follow slavishly and build floors that are thousands of euros more expensive, only to have them dropped again for more thousands. You can also perfectly place a wall outlet above the door.

You can also wonderfully place a wall outlet above the door.

Well, above the door is not exactly optimal for room airflow, keywords short-circuit overcurrent openings. I am rather skeptical about long-throw nozzles, throw distance/airflow noise is an interesting area of tension.

I believed that for a long time as well. Feeding the search engine with "air movements in freely ventilated living spaces".

Quoted from:

There are often unclear or even incorrect ideas among specialists about the air movements within the individual rooms. It is widely believed that supply and exhaust air outlets must be arranged opposite each other in the room layout to ensure uniform ventilation of the room. However, various research projects have demonstrated that heat or cold sources (people, windows, radiators, lighting, appliances) and people’s movements throughout the room lead to a uniform mixing, regardless of the location of the outlets. Only their height is important, in that the exhaust air should be captured near the ceiling.

But even if one questions that, from my point of view the question still remains whether it ultimately makes no difference why exactly the indoor air quality is suboptimal. Whether that is due to insufficient ventilation or to a system turned down because of its noise level – it remains the same.
In the former case, however, one achieves lower distribution losses in any case and saves significantly on installation.