No vapor barrier if the wall has less than 200mm insulation?

[Klicka]

I read that you don't need a vapor barrier if the wall has less than 200mm of insulation?

http://gds.se/spara-energi/isolering/aldrig-mer-osaker-paa-aangsparren

It says:
"Theoretically, this occurs about 200 mm out in the insulation material. If you have less than 200 mm of insulation, as a rule of thumb, the indoor air will first condense on the other side of the insulation, and then it is just ventilated away.

But if you have more than 200 mm of insulation, the condensation occurs within the insulation."

Is this correct?

 

[Micke64]

Spontaneously, it doesn't feel correct. The condensation occurs when the relative humidity becomes too high. Depending on the temperature and humidity on either side, it could very well happen inside the wall. It really shouldn't have anything to do with the distance at all?

 

[Daniel 109]

No. That is incorrect. It is more commonly calculated that the condensation risk is positioned so far out that the temperature corresponds to the indoor air's dew point. However, there are many factors that influence this. If you maintain a constant underpressure in the house and the wall is slightly permeable, dry air will enter through the wall, for example.

 

[Bernieberg]

Spontaneously, it doesn't feel correct. Condensation occurs when the relative humidity becomes too high. Depending on the temperature and humidity on either side, it could very well happen inside the wall. It really shouldn't have anything to do with the distance at all?

I agree. Regardless of the wall construction, the indoor and outdoor air have their temperature and humidity levels. If the dew point is somewhere between these conditions, it will end up in the wall no matter how it is insulated.

I subscribed to that magazine for a while but found quite a lot of inaccuracies and mistranslations of foreign articles.