Partial Controlled Residential Ventilation / Retrofit Climate in the Attic

Ok... too bad... Yes, based on the experiences in the ground floor, I thought I only needed to distribute the air at the top. Because the air conditioning would have enough power to cool the area.

Well, that is one issue, controlled residential ventilation is another. Would this be feasible and sensible as planned? Which device, how many supply and exhaust air ducts, etc.?
I have already contacted a company here with my concerns, but unfortunately have not received a response yet.

summed it up perfectly! A professional company can advise you on-site precisely. Get a local expert for this, who will also make a cost estimate!

Well, nowadays there are unfortunately far too many "experts"! That is exactly the problem. We would also like to do the installation ourselves. We can manage a couple of holes in the ceiling and connect the hoses.

The planning is of course a different caliber! Thank you very much for the feedback!

Well, unfortunately there are far too many "experts" nowadays! That is exactly the problem.

Well, but that is the problem! There are definitely reputable providers in your area. 1-2 inquiries and that's it!

Hmm, so I have contacted some here, but unfortunately have not received any feedback so far. Do you know any reputable online providers who can assist with the planning?

You can also plan with the planning software from Wolf or Helios and other manufacturers, and in principle, the planning is applicable to other systems.