Avoiding Window Condensation in High-Humidity Buildings

October 30, 2008
Publication: Proceedings of RCI 2008 Symposium on Building Envelope Technology
Author(s): Vince Cammalleri Marcin Pazera

Buildings with high relative humidity interiors, including hospitals, laboratories, and indoor pools, frequently experience wintertime condensation along windowsills and other perimeter components. Uncontrolled condensation in exterior envelope assemblies can cause moisture damage and contribute to interior air quality problems. Window perimeter details that are adaptations of conventional building designs frequently cause condensation problems. Installing metal-framed windows directly on exterior cladding elements, for example, short-circuits the thermal resistance of the windows. Understanding the causes of condensation and carefully considering window perimeter details can help prevent these problems. The presenter will summarize common building practices that lead to window perimeter condensation in high-humidity buildings. He will present practical advice to conceive and design window details that avoid condensation.