Condensation - a Sign of Window Performance?

30th May 2024

Condensation is the process of a gas changing into a liquid. It happens when the temperature of the gas falls below its ‘dew point’. On windows it is often a sign of lack of ventilation. However, it may not always be the case and depends on where it takes place.

Condensation - a Sign of Window Performance?

Condensation on the outside of the window
If your windows have excellent thermal insulation and airtightness, after a cold night, the glass panes may mist up on the outside. The outer pane of the window stays relatively cold, and the moisture caused by the temperature difference between the air and window surface, causes mist to form on the outside of the window.

This happens only during morning hours and disappears as soon as the temperature rises.

Condensation on the inside of the window - Ventilate!
If condensation occurs on the inside of the glass pane, it's a sign that the relative humidity inside the room is too high. This is due to water vapours from kitchens, bathrooms or simply breathing! It should be brought down by ventilating the room. Ventilation helps avoiding rot and moisture damage in addition to a poor indoor climate.

Condensation between two glass panes - A punctured window
If condensation is occurring in between two panes of glass, it is a sign that the sealed unit is punctured and should be replaced

If you are looking to upgrade your windows, reach out to us here.

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