Diagnosis
Condensation occurs when humid indoor air cools against cold surfaces like windows. The solution is controlled extraction of that humid air: a system C or demand-controlled C+ in the wet rooms.
Take the ventilation check
Ventilation against condensation
Fogged windows, droplets on the sill and a clammy feeling almost always point to too much moisture combined with too little extraction. Showering, cooking, laundry and even breathing add litres of moisture to the air every day.
What really helps against condensation?
Continuously and specifically extracting humid air from the bathroom, kitchen and toilet works better than opening a window now and then. A mechanical system (C) or demand-controlled system (C+) keeps relative humidity between 40 and 60 percent.
Indoor air
What healthy indoor air means
Ventilation is about invisible air quality. Here is how to recognise healthy values.
CO2ppm
good: below 800attention: above 1200
High CO2 makes rooms stuffy and tiring, often in bedrooms.
Relative humidity%
