Cutting Carbon at Every Stage

Holistic Life-Cycle Analysis at John Lewis Elementary School, Washington, DC

Our holistic carbon life-cycle analysis study at John Lewis Elementary School in Washington, DC, adds to our body of research for our high-performing school projects by diving deep into the whole-life carbon emissions. Through our analysis, we identified the design strategies that resulted in the greatest life-cycle carbon reductions, inclusive of both operational and embodied carbon. The full research was presented at Greenbuild 2024 by Ryan Dirks and collaborators from Carbon Leadership Forum, UC Berkeley, and CMTA. Key findings include: 

• The high-performance design strategies at John Lewis eliminated nearly all operational carbon emissions, largely due to the building’s efficient envelope, all-electric design, and ground source heat pump system (see Figure 1). 

  
  

• At least a 10% reduction in embodied carbon is possible at little to no additional cost. Further embodied carbon reduction requires alternative approaches such as mass timber or the reuse of an existing building. 

  
  

• The greatest life-cycle carbon reductions for building architecture and design come from strategically limiting glazing area, minimizing infiltration, and specifying low-embodied carbon concrete, cladding, and finishes. Different building claddings have significant variation in the amount of embodied carbon per square foot (see Figure 2). 

  
  

• The mechanical, electrical, and plumbing (MEP) team plays a crucial role in reducing both operational and embodied emissions. 

Figure 1: Whole-life carbon emissions of hypothetical designs in comparison to John Lewis Elementary School’s carbon-saving design

Figure 2: Embodied carbon emissions of different exterior wall assemblies