Construction of wooden beam ceiling single-family house 2-story with gable roof.

Hello and Happy New Year!

Without circulation, you would have the "breeding ground" here for exactly the condensation you fear.

Hello 11ant, could you please explain this sentence to me? How do you ensure the necessary air circulation then?

How do you then ensure the necessary air circulation?

Not at all there. Only without it do you get exactly what you want to avoid: the idea of the air layer is not sensible to transfer from the vertical to the horizontal.

Thank you 11ant. I will summarize to see if I understood correctly:

[*]Laying wooden boards directly on the wooden beams is correct; this results in full insulation.
[*]Tongue and groove boards instead of OSB panels on the wooden beams and insulation is a fault-tolerant construction because it is more vapor-permeable, allowing the condensate to evaporate more easily.
[*]The be-all and end-all is a functioning vapor barrier on the lower, warm side.

Did I understand everything correctly, or did I miss something?