What is Embodied Carbon?
Embodied Carbon, the measure of the CO2 emissions resulting from the manufacture, transport and construction of building materials, will account for almost half of total emissions from new construction between now and 2050. Embodied carbon in buildings contributes to approximately 11% of global emissions.
The Boston chapter of AIA has a great video series about Embodied Carbon.
10 Ways to Reduce Embodied Carbon
  1. Reuse buildings instead of constructing new ones. 

  2. Specify low-carbon concrete mixes. 

  3. Limit carbon-intensive materials. 

  4. Choose lower carbon alternatives.

  5. Choose carbon sequestering materials. 

  6. Reuse materials. 

  7. Use high-recycled content materials. 

  8. Maximize structural efficiency. 

  9. Use fewer finish materials.

  10. Minimize waste. 

By taking these steps upfront, architects can make a big impact during the building stage of a project.

Bringing Embodied Carbon Upfront
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World Green Building Council's Vision:
By 2030, all new buildings, infrastructure and renovations will have at least 40% less embodied carbon with significant upfront carbon reduction, and all new buildings must be net zero operational carbon.
By 2050, new buildings, infrastructure and renovations will have net zero embodied carbon, and all buildings, including existing buildings, must be net zero operational carbon.
Embodied Carbon Benchmark Study: LCA for Low Carbon Construction

The Embodied Carbon Benchmark Study provides data to building industry professionals integrating embodied carbon into life cycle decision making. This report outlines the first stage of the project, which establishes reasonable estimates of the embodied carbon of buildings (the greenhouse gas emissions resulting from extracting, manufacturing and installing materials and products over the life cycle of a building) and characterizes the level and sources of uncertainty in our current knowledge.The research team identified four main findings and limitations, which are detailed below:

  1. Finding A: The data presented in the RESEARCH database represents a reasonable order of magnitude and range of variation of estimates of the embodied carbon footprint of buildings.

  2. Finding B: The initial embodied carbon (LCA stage A) of a building’s structure, foundation and enclosure is typically less than 1,000 kgCO2e/m2.

  3. Finding C: The initial embodied carbon (LCA stage A) of low-rise (less than 7 story) residential building’s structure, foundation and enclosure is typically less than 500 kgCO2e/m2 however there is not sufficient data to state ranges with confidence.

  4. Finding D: For commercial office buildings, the range of initial embodied carbon (LCA stage A) for building structure, foundation and enclosure is between 200 and 500 kg CO2e/m2 for 50% of buildings in the database.

Embodied Energy: 
Just What is it and Why Do We Care?
Almost all the attention paid to energy conservation in buildings has focused on reducing their operating energy. Given the energy hogs that many buildings were (and are), this focus is appropriate. As builders and architects succeed in making their buildings more efficient, however, the energy used to build buildings starts to look significant. This embodied energy can add up to many years’ worth of operating energy in an efficient building (see table). While taking steps to reduce operating energy is clearly the first priority, it makes sense to look for options that minimize the initial energy investment—the embodied energy—as well.
Life Cycle Assessment of Buildings:
        A Practice Guide

Embodied Carbon Benchmark Study identified a need in the industry for standardized and accessible guidance on how to conduct an LCA of a building.  The LCA Practice Guide was developed to address this need.  The LCA Practice Guide and supporting files are provided below:

  • Practice Guide: This is the primary document of the LCA Practice Guide.  It introduces the concept of life cycle assessment to building professionals and explains how to determine the environmental impacts of a building step by step.  Version 1.1 (June 2019) is the second update following the original publication in June 2018 and contains a roadmap diagram, which is also provided separately below. Click for download.

  • Road Map to Reducing Building Life Cycle Impacts: This timeline contains suggested actions and milestones for reducing building life cycle impacts. There are two versions: 2-Page Document and Full Page Document

  • Technical Guidance: This document is directed at LCA experts who are looking for technical recommendations to support the development of LCAs of buildings in North America.  Note that the version dated 2018-07-09 has the same content as the version dated 2018-06-19, but with different title page formatting that includes sponsor logos. Click for download.

  • Taxonomy for Whole Building LCA: This is a proposed information scheme for reporting information relating to LCAs of buildings, Goal and Scope sections. Click for download.

  • Gingerbread House LCA Example: This is a simple example demonstrating the LCA process using a gingerbread house. Click for download.