Conventional Roof Assemblies: An Update to a Five-Year Field Monitoring Study
Presented by Lorne Ricketts, PEng of RDH
A long-term field monitoring study has measured the impacts of membrane color and insulation strategy on the in-situ performance of conventional roof assemblies. The same roof membrane cap sheet type with three different surface colors (white, gray, and black) was installed over three different conventional insulation strategies with approximately the same R value, creating a total of nine unique roof assemblies on the same building. Sensors were then installed to monitor key performance indicators for the roofs, including temperature at key layers of the roofs, relative humidity within the assemblies, and solar reflectance of the roof membranes.
This paper presents the results of this monitoring work after five years of study. In particular, updates and further analysis are presented with respect to moisture movement and accumulation within the assembles, insulation performance, and long-term reflectivity and soiling of the roofing membranes. Exploratory openings are also to be performed to confirm results of the monitoring and collect samples for laboratory testing of the roofing materials post field exposure. The various measurements are analyzed and synthesized to allow for discussion of advantages and disadvantages of the different membrane colors and insulation arrangements.