What is Dew Point and Why is it Important?
There is a maximum amount of water vapour that can be suspended in the air and it varies according to the temperature. When this limit is exceeded the water vapour becomes liquid. So when the air is cooled and moisture capacity is reduced, the air saturates, excess vapour condens and become liquid water as described above. This temperature is the dew point of that certain conditions.
When there is unwanted condensation in between some layers of the facade system, there is a risk for human health and performances of the building such as durability and insulation. Therfore such condensation must be prevented by calculating via using the climate conditions, design temperature and relative humidity.