What causes condensation on the inner surface of storm windows?
All operating windows leak some air between the window frame and sash. So when warm household air seeps in around the sash and becomes trapped by the colder storm window, condensation forms on the inside surface. Providing outside ventilation to the combination storm window can usually reduce condensation buildup. What causes moisture to form on the outside of the windows? It’s dew, the same condensation you see on windshields. lawns and streets on many mornings. Condensation like this happens only when the exterior surface temperature of the glass falls below the dew point of the air. When humidity levels are higher, this kind of condensation is more likely to form. Most of the time, exterior window condensation takes place in the Spring and Fall, when cool nights follow warm days. Can excess condensation damage windows? Excess window condensation can cause paint to peel from the sash. Excess moisture can also damage the window frame. Is exterior condensation anything to worry about?
