Controlled residential ventilation planning: position of components; length of ducts

These foam pipes with an inner diameter of 160 mm have an outer diameter of 190 mm.

I would be cautious and not press foam pipes/insulation pipes in a ring space sealing. The risk of damaging the pipe would be too great for me. Better to switch to KG2000 or Awadukt pipe inside the house just before the wall. That can be routed through the wall without any problems.

I can't say that. I would always prefer the floor valves over all other variants.

I dislike digging up topics again, but I would like to hear arguments why the floor is preferred? Does that then apply to both supply and exhaust air? Against the floor would be the "suction" of dust and the stirring up of dust and the issue of furniture.