Mold in living spaces is not only an aesthetic problem, but can also lead to health problems. Excessive humidity in these places is often only recognized when it is already too late. A hygrometer and consistent ventilation can help reduce the risk.
Ventilation is not the same as ventilation
Shock ventilation with windows wide open is ideal for quickly replacing the air that arises, for example, from unpleasant smells in the kitchen or toilet.
The situation is different with the moisture that occurs after showering, bathing, cooking or sleeping, as moisture is still stored in the wall surfaces, towels, mattresses or duvets. Here it is better to ventilate completely and then leave the window open for two to three hours so that this “sorption moisture” goes out. The associated energy loss is small as long as the windows are not tilted around the clock. The room drying effect, on the other hand, is significantly greater than with three shock ventilations, as measurements show.
The claim that the walls cool down when they are tilted for longer periods only applies to the window reveals. However, this is not critical, as these reveals also become significantly drier during ventilation. Mold in window reveals is primarily a thermal bridge problem and not a tilt ventilation problem.
- Tip : Damp towels can be hung outside even when it's frosty. Because cold air is dry air. It just takes a little more patience.
Humidity is not the same as humidity
To determine whether a room is too humid, a hygrometer in combination with a thermometer helps. The optimal air humidity also depends on the building structure and insulation.
In an uninsulated old building, 25 to 45 percent relative humidity is OK; in a very well insulated new building it can be 35 to 55 percent. However, the room temperature must always be taken into account, because colder air can absorb less moisture.
If the relative humidity rises again after just a few minutes after ventilation, this is an indication of high humidity in the affected room. This is often found in materials such as wallpaper or furniture. Such a room can be completely dried through targeted heating and ventilation.
- Tip : When ventilating the room, the heating should be turned down well in advance. The savings effect is greatest when the hot water in the radiators has already cooled down.
Conscious heating helps prevent mold and save energy
In order to save energy, you can lower the room temperatures, but sufficient ventilation and control of the humidity in the rooms are crucial. It is also important to keep doors closed between rooms that are heated at different temperatures so that moist air does not migrate into cooler living spaces and cause or exacerbate a mold problem. Radiators should not be covered by panels, furniture or curtains. This is the only way the performance can be fully utilized and the thermostatic valve can function optimally. In addition, the right temperature should be selected for each room:
- 18 to 20 °C is sufficient in the living room and kitchen,
- in the bathroom it should be 20 to 22 °C,
- while in the bedroom 18 °C ensures a comfortable sleep.
At night and during the day when no one is home, the overall temperature can be reduced. How strong depends on how high the humidity level is in the apartment. The drier the apartment is, the lower the temperature can be. Therefore, you should always look at the humidity and temperature together, ideally with the help of a thermo/hygrometer that displays both variables at the same time.
- Tip : Cool rooms should not be heated with air from warmer rooms and interior doors between differently heated rooms should always be kept closed. Otherwise the moisture will enter the cool room as heat and the relative humidity and the risk of mold will increase.
Free online seminars “Prevent and eliminate mold”
The Lower Saxony Consumer Center provides independent information to those affected and interested parties in free online lectures on the topic of “ preventing and eliminating mold” There are currently three dates to choose from:
- February 24, 2023, 3:30 p.m. to 5:00 p.m.: Recognizing, eliminating and avoiding mold, speaker: Dipl. Biologist Holger Glaus
- March 2nd, 2023, 5:00 p.m. to 6:30 p.m.: Beware of mold infestation! Structural damage or user behavior? , Speaker: Dipl.-Ing. Florian Lörincz
- March 3, 2023, 4:00 p.m. to 5:30 p.m.: Mold and thermal insulation, a contradiction? Speaker: Dipl.-Biologist Holger Glaus
Further information on the subject of mold and registration for the online lectures can be found at www.verbraucherzentrale-niedersachsen.de/veranstaltungen-Schimmel-vermeiden-und-belegenen
Source:
Lower Saxony Consumer Center
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