Proper ventilation prevents the formation of water condensation in living areas and particularly at windows. The less air exchange takes place with the outside air, the more humid the indoor atmosphere is. The colder the outside air is, the drier the indoor air becomes. The more humid the indoor air and the colder the surface of a component, the greater the risk of water condensation forming. Proper ventilation (intermittent ventilation) saves energy, is more hygienic, and avoids moisture damage.
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At a room temperature of 20°C and 60% relative humidity, one cubic metre of room air binds 10g of water. When cooled to 8°C, the room air only binds half that quantity of water, with 50% precipitating on the external walls as water condensation.
20°C / 60% relative humidity
1m3 room air
8°C / 60% relative humidity
Water bound in the room air: 5g
Water bound in the room air: 10g Condensation
High-quality aluminium windows from SwissStarFenster AG have excellent airtightness. For a good indoor atmosphere, however, it is important that a complete change of the room air takes place regularly.
Because warm air can absorb a significantly higher quantity of moisture than cold air, high humidity often precipitates in the form of water condensation at cold points such as external walls, window niches and window glass. In order to avoid the formation of mildew, it is therefore necessary to ensure drying through consistent ventilation.
This is best achieved by means of intermittent ventilations with fully opened windows several times per day.
Ventilation is necessary for reasons of hygiene and health. Regular ventilation discharges the gases, odours and high humidity that result from use. Structural damage that can occur due to the formation of condensation resulting from excessive humidity levels can be avoided by means of proper ventilation. The relative humidity in indoor areas is heavily influenced by the exchange of air.
As a point of reference, it is recommended that the entire volume of air in the room is exchanged with the outside air once every two hours. Ventilation is particularly effective in winter, because low temperatures have low humidity levels. When entering the room, this air is warmed up and the relative humidity falls. With airtight windows, natural ventilation in the closed state is not sufficient to ensure the necessary exchange of air.
VENTILATION TIPS / EVEN ON COLD, WET, MISTY DAYS, THE RELATIVE HUMIDITY OUTSIDE IS SIGNIFICANTLY LOWER THAN IN WARM INDOOR SPACES. BY MEANS
OF REGULAR INTERMITTENT VENTILATION, YOU CAN KEEP THE HUMIDITY IN YOUR ROOMS AT A COMFORTABLE LEVEL OF 40 – 60%. FURTHERMORE, IN CONTRAST TO
CONTINUOUS VENTILATION WITH TILTED WINDOWS, INTERMITTENT VENTILATION SEVERAL TIMES PER DAY RESULTS IN LOWER LEVELS OF HEAT LOSS IN YOUR ROOMS.
Sornpark 1 · 9246 Niederbüren · Switzerland
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