Two years ago, I took a class with the architecture department called Vernacular and Adaptive Reuse. This class examined many of the topics discussed in the Preservation Green Lab’s ‘The Greenest Building: Quantifying the Environmental Value of Building Reuse.’ The class discussions evolved around the important environmental, economic and social benefits of building reuse.
I became really interested in embodied energy and understanding a building’s Life Cycle Assessment (LCA) while taking this class. Our final project had us dissect an older (pre-1960s) building within the Seattle area to determine its embodied energy. The second phase of the project had us determine the energy required to demolish the existing building and construct a new building on the same site maximizing the highest square footage per zoning and building codes. While this was a valuable exercise in understanding the logic behind the LCA, I learned about the challenges of achieving an accurate calculation in older buildings.
First, drawings. Architectural and MEP drawings provide the building’s guts. They tell you how the building was built, with what materials, at what dimensions, and where and how systems work. We found that many building owners, particularly in older buildings that have exchanged owners throughout its course, rarely own the original building drawings. They could usually always provide a floor plan, but usually not one with enough detail to make a LCA calculation very accurate. For instance, why would a restroom remodel from the 1980s tell us how deep the foundation pour is for a building construction in the 1940s? It doesn’t, nor should it. But, in reality, most owners for all of our case study buildings only had drawings showing recent renovations within the past 20 or so years. Without the original drawings (or a massive due diligence of the existing building), a building’s embodied energy and LCA are no more than just an educated guess.
Second, the Athena EcoCalculator. While my exposure to the calculator was limited, probably 10-15 hours during a two-week period, I did find the calculator to be very broad and too general. Buildings are complicated in nature. The Athena EcoCalculator does not have enough flexibility for all the ‘but’ and ‘what if’s’ that buildings often have. While it’s a good tool, I thought the calculator needed more development in its offerings and options. With better drawings, the EcoCalculator can be more effective; therefore, promoting more credibility in its accuracy.
My intention is not to undermine the importance of a building’s embodied energy. Case studies have proved time and time again that keeping an existing building and reusing its shell have great environmental and social repercussions. My intention is more focused in hopes to reveal the complexity of acquiring necessary data to provide accurate results.