Draft through the sockets

Hello,

I have insulated and converted my attic over the past year. From inside to outside: drywall, 50mm mineral wool, vapor barrier, 180mm mineral wool, underlay membrane. Before I installed the drywall, you could see the vapor barrier move in strong winds. I thought that was okay, after all, it is the airtight seal to the outside, which I carefully connected to the walls and the floor.
Now I noticed that there is a draft through the sockets and cable penetrations in the ceiling when the weather is windy.
Could this be the overpressure forming under the drywall when the wind presses against my insulation? Has anyone else observed this elsewhere?

I would be happy to receive a reply.

Regards

Hi,

......you could see how the vapor barrier moved in strong wind. I thought that was okay, after all, it is the air seal to the outside,

The wind should not even get that far to set your insulation and vapor barrier in motion.
The vapor barrier is the airtight layer that is supposed to prevent moist air from the rooms from entering the construction. On the outside, there is still the windproof layer, which is the so-called or also underlayment membrane that is supposed to protect the entire construction, among other things, from wind.
If your insulation and vapor barrier are fluttering in the wind, there are certainly some connection errors somewhere, but these cannot be found here or remotely, of course.

Regards

Thank you for the quick response. I installed the insulation in the roof structure afterwards. Therefore, I attached the underlay membrane from rafter to rafter, only at the floor height where the insulation is also located. The underlay membrane ends in the uninsulated attic. Therefore, it is probably not a windproof layer; it rather protects the mineral wool from potential raindrops that find their way through the roof tiles and bitumen sheets. Regards

Unterlay membrane must of course be pulled up to the ridge. Are your tiles lying on roofing battens? Have you then installed a ventilation gap? Roofing battens are not vapor permeable.

Hello, I have installed ventilation. I further tested in front of the sockets: Held a lighter in front of the sockets and opened and closed the room door normally. Each time a draft occurs there that sometimes blows out the flame. However, the sockets are also installed in the hollow sloping wall. Maybe the whole thing is normal? Regards

Maybe the whole thing is normal after all?

No, certainly not