The Life CycleAssessment (LCA) Group is working toward educating structural engineers on the meaning and professional application of LCA criteria, procedures, and measurements in order to make environmentally conscience decisions on the use of structural materials.
Life cycle assessment (LCA) is a method of measuring the total environmental impact of a product or process, from acquisition of raw materials to end-of-life. For structural materials, the life cycle generally includes extraction, manufacture, transport, construction, maintenance, re-use and recycle opportunities and end-of-life including demolition and disposal. Thus LCA provides the most complete picture of environmental effects inherent to choosing certain structural materials. It is analogous to performing environmental accounting on the structural materials in order to choose the most environmentally friendly design solution over the anticipated standardized life of such materials.
LCA has four basic stages or evaluation components; goal and scope definition, inventory analysis, impact assessment, and interpretation. The inventory analysis can utilize such catalogs as the U.S. Life-CycleInventory Database prepared by the National Renewable Energy Laboratory, and the Inventory of Carbon and Energy ('ICE') prepared by the University of Bath. The analysis can be done in software programs such as Athena Eco-Calculator and the SimaPro. In addition, some companies are coming out with their own proprietary software for post processing the data and inventories based upon specific circumstances.
LCA assessment tools move beyond simplistic assumptions and determine true environmental impacts. Measurements of LCA include multiple metrics including quantifying the environmental ‘costs’ (e.g. CO2emissions) of each item, the energy required to produce the items (embodiedenergy) and various measurements of how these impacts relate to larger scale environmental concerns (e.g. global climate change)
The main goals of the group include:
1. Providing information and resources to the structural engineering community on applications of LCA in building and infrastructure design.
2. Improving LCA software to better represent environmental impact reductions we know can be made from structural design and specification.
3. Engaging structural engineers in the incorporation of LCA into green building and infrastructure rating systems and building codes.
Currently, the group is working on publishing their response to the top 10 most encountered questions, as experienced by LCA Committee members within their practice of structural engineering.