Window Fogging Up Inside – How to Prevent Condensation

Condensation on window panes forms when warm, humid indoor air meets the cold glass – a sign of excessive humidity or insufficient ventilation. Solution: Ventilate thoroughly 2–3 times a day for 5–10 minutes each time by opening windows wide (rather than leaving them on the tilt setting). Keep room temperature consistent and avoid drying laundry indoors. A hygrometer (approx. £5–10) is helpful: the ideal range is 40–60% relative humidity. If only the outer pane of a double-glazed window fogs up persistently, or if condensation appears between the panes, the glass seal is faulty – contact a glazier or qualified professional in that case.