The formation of ice on the interior surfaces of residential windows is a phenomenon resulting from a confluence of factors: high indoor humidity levels, low outdoor temperatures, and insufficient window insulation. Condensation initially forms on the cold window pane, and when the temperature drops below freezing, this condensation solidifies into ice. An example would be visible ice crystals forming on the inside of a homeowner’s bedroom window during a prolonged period of sub-freezing weather.
Addressing this issue is crucial for several reasons. Excessive indoor humidity can promote the growth of mold and mildew, leading to health problems and structural damage. Moreover, the presence of ice indicates significant heat loss through the windows, resulting in increased energy consumption and higher heating bills. Historically, older homes with single-pane windows were particularly susceptible, but even newer homes can experience this problem if ventilation is inadequate or window seals are compromised.