Number of air vents

hm.?

What is actually the best recommended solution?
Supply and exhaust air (each separately in the different rooms) at the ceiling or in the floor?

Regards and thanks in advance, scooter.

The best solution for positioning is:

The room must be able to be ventilated... either supply or exhaust air as far away as possible from the door... or if supply and exhaust air are in the same room, then as far away as possible from each other and preferably not on the same wall/ceiling etc. depending on the size of the room this rule must of course be relativized...

Speaking of floor valves... even if something goes wrong occasionally, it is usually not a problem...

By the way, the number of valves is negligible as long as the system has been properly calculated...

hm.?

What is actually the best recommended solution?
Supply and exhaust air (each separately in the different rooms) at the ceiling or on the floor?

Greetings and thanks in advance, scooter.

Opinions probably differ - there are all kinds of solutions ;-)
If the system is properly calculated, it probably doesn’t matter.
In our case, the exhaust valves are always located at the top (ceiling or wall) and the supply air comes from the floor in front of the floor-to-ceiling windows.
Visually, it really doesn’t matter. The exhaust grilles are white and round, the supply air grilles are made of visually very appealing stainless steel and are rectangular.

How is (putting the optics aside ;-) the best airflow - without drafts - to be achieved?
Supply air through wall or ceiling outlets in the supply air rooms at the top and the exhaust air through the door gaps at the bottom - via the exhaust air on the ground floor from the kitchen and upper floor from the bathroom through ceiling or wall exhaust air vents?
Or with the same exhaust air - the supply air through the floor outlets?

Well, the air volumes are actually not so large that one could call it a draft in a single-family house

Ok. Just for the best flow or air exchange, I meant ;)