From May to November of 2015, the majority of the windows in the Yanke Family Research Park (i.e. the Yanke Building) were removed and replaced with modern high-quality windows because many of the exiting windows had failed and fogged. While such a retrofit should result in significant energy savings, there remains a possibility that improper integration of the new window systems to the building structure may degrade performance by inadvertently providing paths for infiltration of outside air or by providing “bridges” of relatively high thermal conduction between the conditioned space and the environment. In an effort to assess the impact of the retrofit, researchers at the CAES Energy Efficiency Research Institute (CEERI) analyzed the energy consumption before and after the window retrofit, using industry standard techniques to normalize consumption to prevailing weather conditions.