This research explores and advances three key areas relevant to the field of buildings LCA: methodology, benchmarking, and impact reduction opportunities.
The methodology is applied to three classes of existing benchmark buildings: a 12-story, 498,590 ft2 commercial building; a 33,763 ft2 four-story multifamily building, and a two-story, 2,400 ft2 single family house.
The buildings are analyzed for two climates, Phoenix and Chicago, and for different structural materials. The commercial building is analyzed for a concrete structure and a steel frame, while the residential buildings are compared for insulated concrete form (ICF) and wood construction.
The annual operating energy is projected to be constant over a 60-year analysis period. The Global Warming Potential (GWP) is quantified using CO2-equivalent (CO2e) for a number of purposes, including benchmarking emissions for current practices, comparing concrete with competitor materials, and understanding the relative importance of different phases of the life cycle.
This analysis demonstrates that the greenhouse gas emissions due to operation energy of buildings are typically responsible for 88%-98% of life cycle emissions. Compared to wood or steel structures, concrete buildings typically have equal or higher embodied emissions, but have lower operating emissions, which can lead to similar life cycle emissions over time. For all cases considered, concrete buildings have similar emissions over 60 years as steel and wood alternatives.
Finally, a range of options for reducing life cycle emissions are considered for each concrete building type.