{"id":5285,"date":"2026-11-13T19:51:45","date_gmt":"2026-11-13T18:51:45","guid":{"rendered":"https:\/\/aristofenster.eu\/window-condensation-ventilation\/"},"modified":"2026-11-14T05:48:00","modified_gmt":"2026-11-14T04:48:00","slug":"window-condensation-ventilation","status":"publish","type":"post","link":"https:\/\/aristofenster.eu\/en\/window-condensation-ventilation\/","title":{"rendered":"Window Condensation: Causes and How to Ventilate Properly"},"content":{"rendered":"

In the morning the pane is misted up and droplets collect on the frame \u2013 condensation on windows is a common nuisance in winter. Whether it is harmless or a sign of a problem depends on where<\/strong> the water forms. We explain the causes and show you how to ventilate properly.<\/p>\n

Why does condensation form?<\/h2>\n

Warm air can hold more moisture than cold air. When moist indoor air meets a cold surface, it cools down and the moisture settles as water. The temperature at which this happens is called the dew point<\/strong>. The higher the humidity in the room and the colder the surface, the more likely condensation becomes.<\/p>\n

Three cases \u2013 three meanings<\/h2>\n

Condensation on the inside of the pane<\/h3>\n

This is the most common case. It is usually caused by excessive humidity \u2013 from cooking, showering, drying laundry or lots of plants \u2013 combined with a cold glass surface. Old windows are particularly affected, as is the edge of the glass if it has an aluminium spacer. Modern windows with triple glazing and a warm edge spacer<\/strong> have much warmer inside surfaces.<\/p>\n

Condensation on the outside of the pane<\/h3>\n

If the pane mists up on the outside in the morning, that is a good sign: the glazing insulates so well that the outer pane receives hardly any heat from inside and cools down considerably at night. This mainly happens in autumn and disappears as soon as the sun warms the glass.<\/p>\n

Condensation between the panes<\/h3>\n

If moisture forms in the cavity between the panes, the edge seal is leaking. The insulated glass unit has then lost its insulating effect and should be replaced.<\/p>\n

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Misted windows? We can help.<\/p>\n

We check whether your windows are still up to date and advise you on glazing, warm edge spacers and ventilation.<\/p>\n

Get advice \u2192<\/a><\/div>\n

How to ventilate properly<\/h2>\n