Regional variation of greenhouse gas mitigation strategies for the United States building sector

In this study, the impacts of various mitigation strategies for existing and newly constructed buildings in the United States on embodied and operational greenhouse gas (GHG) emissions were quantified until 2050. A bottom-up approach was utilized to model the characteristics of individual reference buildings. First, reference designs and practices were developed for climatic regions across the United States to capture spatial variation in energy demand, building codes, and structural performance. Then, the results were scaled up to regional networks (at county and state levels) and finally to the entire country. Given the fact that mitigation strategies can vary by region and building type, we explored the key drivers of impacts in the buildings sector and prioritized which strategies should be applied in different regions and building types. To meet deep decarbonization goals, we will need to pursue strategies for GHG emissions reductions in both the embodied and operational phases of the building life cycle. We found there will be no meaningful reduction in building GHG emissions in the Western US and New England regions under current projected technology and code improvements because they are on the leading edge of emissions reduction strategies. However, there is much more opportunity to lower life cycle GHG emissions in the Midwest and central US regions because they are further behind the implementation of reduction strategies. A number of interventions—chiefly to the electricity grid, appliances, and lighting—could nearly halve the emissions of new buildings constructed between 2016 and 2050.