RCI: Condensation Risk of Mechanically Attached Roof Systems in Cold-Climate Zones
"Flat roofs generally have a high potential of nightly overcooling and, therefore, an increased risk of condensation within the construction, particularly in cold-climate zones, depending on their specific assembly. A white exterior surface or so-called “cool roof,” applied to decrease cooling loads and to save energy, increases the condensation risk due to lower energy gains during daylight hours. There have been questions raised about the sustainability of using cool membranes in northern U.S. climate zones due to the potential of moisture accumulation below the membrane. Transient hygrothermal simulation using real climate data is state-of-the art today and can help to study different effects. results will be shown."
Author: Manfred Kehrer, Oak Ridge National Laboratory
Author: Simon Pallin, LicEng, Chalmers University of Technology, Sweden