Life cycle assessment (LCA) is a tool to quantify the environmental impacts of a product or system. This tool is used to assess environmental impacts of buildings over their lifespan. LCAs performed on standard buildings showed that the use phase dominated the impacts over the course of a building's lifespan. Consequently, building energy efficiency was the target of reduction measures and high-performing buildings began to emerge. The design of living buildings followed, which are buildings that are defined as being net-positive energy and water. In these energy efficient buildings the significance of the use phase diminishes, shifting the focus to other life cycle stages. This research includes a whole-building LCA of a living building that focuses on the impacts from green building materials, a decentralized water system, a net-positive use phase, and the disposal of structural materials. The material processes used in this LCA were modified by removing the use of highly toxic chemicals per the product submittals; results showed carcinogenic impacts were decreased by up to 96%. The septic system, which is not aerated, used for wastewater treatment contributes to 37% of the global warming potential (GWP, kg CO2eq) for the whole building's lifespan due to methane emissions. The solar panels on-site generate more electricity than the site demands, allowing for 44,000kWh of green energy to be returned to the grid. Lastly, a scenario analysis was performed on multiple waste streams for materials of two structural models (lumber or steel) with a concrete foundation. Results showed that based on the frame and waste stream selected, the end of life GWP impacts could vary from +14,000kg CO2eq to-10,500 kg v CO2eq for the as-built structure. This whole-building LCA aims to identify and mitigate hotspots of the case study building, and to reduce life cycle impacts of living buildings moving forward. vi TABLE OF CONTENTS
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.