ᐅ Insulating the Attic Space: How to Avoid Common Mistakes?

So, we don’t have any windows up there. It’s really just a tiny attic. But on each of the two walls, there is a ventilation pipe for cross-ventilation!

Then it mainly depends on the amount of water vapor produced, the water vapor diffusion resistance of the building components involved, and the volumes. Since the roof will be resistant to driving rain, the small ventilation will not be sufficient, as the roof structure is always affected by moisture.
It is no coincidence that insulation of the top floor ceilings is often discouraged in particularly protected buildings.
A simple measurement on the wooden components will provide clarity before the beams turn green.

Watertight does not mean less draft.

My roof is watertight, but there is a strong draft.

Under the eaves, there is simply an open section, with only animal protection mesh installed there.

If there is a draft, insulating is pointless. If you insulate, make sure it is airtight. With all the advantages and disadvantages.

@apokolok

Of course, the underlay membrane reduces air exchange, as indicated by the Sd value of the membranes. Any ventilation, if present, takes place externally, such as at the roof overhang.

However, the question of insulating the attic space becomes completely pointless if the roof cavity is continuously ventilated.