Commercial building retrofits present a prime opportunity to improve building energy efficiency. This is increasingly happening, but usually through simple upgrades of individual building components such as equipment or lamp replacements. These equipment- or component-level retrofits, however, have been shown to have less potential for whole building energy savings as compared to comprehensive system-based approaches (Regnier et al. 2018a). A system-based approach goes beyond a single component, such as by incorporating additional elements or controls within an end use system, or leverages interactions with other building components or end use systems to achieve deeper levels of energy savings. Systems retrofits hold the potential for much greater savings and are critical to achieving aggressive energy reduction goals in the existing commercial building stock.