M.1 Life Cycle Assessment of Building Assemblies

Intent
To set a modest benchmark of performance and inform early building assembly material choices using life cycle assessment of alternatives. Building assembly choices significantly affect global warming, air pollution, water pollution, energy use, and waste.

Required Performance Criteria

1. Meet LCA Benchmark for Total Assemblies GWP (Global Warming Potential)
   During schematic design, use the B3 Guidelines Tracking Tool to determine a custom benchmark for total assemblies global warming potential. Perform a material lifecycle analysis of project building assemblies using Athena EcoCalculator (a free download, see tracking tool) to arrive at a compliant selection of assembly materials that meets the custom benchmark determined in the tracking tool. Enter the compliant design solution and upload the EcoCalculator file to B3 Guidelines Tracking Tool. Note that while the custom benchmark is derived from benchmark values for each assembly type, that compliance depends on the total of all assemblies, meaning that a better performing assembly in one area can make up for a worse performing assembly in another area. Assemblies to be documented are foundations & footings, columns & beams, intermediate floors, exterior walls, windows, interior walls, and roof. Compliance is based on Global Warming Potential, but other important factors to consider in the output are: Energy Consumption, Material Resource Use, Acidification Potential, Human Health Respiratory Effect Potential, Aquatic Eutrophicatoin Potential, Ozone Depletion Potential, and Smog Potential. The analysis is calculated over a 60-year life cycle. Teams may alternately run the Athena Environmental Impact Estimator to model a design solution for a more customized approach.

Recommended Performance Criteria

2. Conduct LCA on Additional Materials
   Use BEES or other tools to perform similar types of analysis for interior finish materials. This type of assessment usually occurs in the DD or CD phase.

Compliance Tools and Resources

For Item A above:

• The Athena EcoCalculator for Assemblies for Minneapolis—Free Download from the Athena Institute www.athenasmi.org
• Alternately: The Environmental Impact Estimator—software from the Athena Institute www.athenasmi.ca

For Item B above:

• BEES (Building for Environmental and Economic Sustainability) software (www.nist.gov/el/economics/BEESSoftware.cfm)