Overview
- This week’s coverage reiterated official guidance that living spaces should aim for about 40–60% relative humidity with poorly insulated homes targeting the lower end and a sustained indoor humidity above roughly 70% treated as a clear warning sign for mold.
- After showering in a bathroom with a window, keep the door closed and open the window for a short, vigorous ‘Stoßlüften’ of about 3–10 minutes so moist air goes straight outside; windowless bathrooms need properly sized mechanical exhaust fans with an appropriate after‑run.
- Cold spots such as exterior wall corners, window reveals and areas behind large furniture act as thermal bridges where surface humidity can reach 70–80% and allow mold to grow even without visible condensation, so check them with a hand test or an infrared thermometer.
- Everyday moisture sources — showers, indoor clothes drying and overnight breathing — raise room humidity, so avoid indoor drying when possible, use a squeegee and rapid ventilation after wet activities, track levels with a hygrometer, and consider a dehumidifier when ventilation alone cannot control humidity.
- Measurement tools help but have limits: place hygrometers centrally, mind IR thermometer emissivity and distance rules, weigh dehumidifier energy costs, and seek professional inspection for recurring damp, deep-seated mold, or suspected thermal-bridge fixes guided by DIN and UBA recommendations.