Development of a Construction Materials GHG Database: Case Study of Concrete

Corinne Reich-Weiser*, Climate Earth/UC Berkeley
Chris Erickson, Climate Earth
David Dornfeld, UC Berkeley

The construction industry is a significant contributor to global greenhouse gas (GHG) emissions and requires comprehensive enterprise-wide life-cycle assessment tools for effective decision-making and design. In 2002, direct emissions and electricity use by the construction industry produced approximately 2% of total U.S. GHG emissions1; however, approximately 70-80% of emissions associated with construction are unaccounted for by this figure, including the mining, processing, and transportation of materials upstream of the construction site2.

LCA tools/databases for the construction industry are currently limited in scope and provide incomplete insight for design modifications. Additionally, the primary standard for “green” buildings in the U.S. is LEED, which provides only qualitative guidelines for building material choices and may not reduce lifecycle environmental impacts3.

Through ongoing collaboration with Webcor Builders Inc., a construction materials GHG database is being developed. In this presentation, a hybrid methodology for development of the Construction Materials GHG database is demonstrated through a case study of concrete. Consistent with an iterative hybrid methodology4, concrete has been chosen as a starting point for the database because it accounts for between 5-15% of new construction GHG emissions2. Initial concrete numbers to refine the input-output database are being developed through work with Central Concrete Supply Co, Inc., a US Concrete Company.

The database development will follow the following process: (1) hybrid LCA of construction using the CEDA 3.0 input-output database2, (2) selective data refinement and expansion through supplier hybrid LCA, (3) hybrid LCA of construction using refined database (4) iterate steps 2 and 3. The methodology provides the opportunity for a comprehensive database incorporating both sub-contractor and materials impacts into a building LCA. This iterative hybrid methodology will enable the database to be refined over time and historical assessments to be updated in real-time.

References

1. Truitt, P. (2009) “Potential for reducing greenhouse gas emissions in the construction sector” U.S. Environmental Protection Agency
2. Suh, S. (2004) Comprehensive environmental data archive, CEDA 3.0 database, IERS, MN, USA.
3. Scheuer, C.W. and G.A. Keoleian (2002) “Evaluation of LEED Using Life Cycle Assessment Methods” United States Department of Commerce, National Institute of Standards and Technology.
4. Tukker, A., P. Eder and S. Suh (2006) “Environmental Impacts of Products Policy Relevant Information and Data Challenges” Journal of Industrial Ecology, 10(3), pp.183-198.
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