The following post is by Kathleen O'Brien:
New is not always better.
I have to confess that I've been a little put off by local historic preservationists self-righteously declaring that "preservation" equals sustainability and leaving it at that. Yes, yes, I understand that recycling buildings intuitively makes sense, but since sustainability sometimes asks us to think counter-intuitively, I needed more. At a recent Sustainable Cities Roundtable conducted by King County's Green Tools Program, I got what I needed.
Robert Young, PE, LEED AP, is professor of architecture and director of the Historic Preservation Program at the University of Utah, and author of the new Island Press release, "Stewardship of the Built Environment." He was guest speaker at the Roundtable. Young provided some very satisfying arguments for promoting preservation and building reuse as a sustainability strategy. In making his arguments, he gives equal weight to what he terms SEE (or what some of us have called the "three E's"): social, economic, and environmental factors, and defines stewardship of the built environment as "balancing the needs of contemporary society and its impact on the built environment with the ultimate effects on the natural environment."
The Historic Preservationists have been at their best when justifying conservation due to social factors, and Young does speak to this. What I appreciated is that he also addresses environmental and economic factors in an analytical but highly accessible manner. One of the areas he touched on in his talk was the idea of calculating energy recovery as part of understanding the energy performance of preservation vs. new construction. As Young notes in his book, "the argument for measuring embodied energy to justify the retention of a building is (still) met with skepticism." He claims this is largely because embodied energy is considered a "sunk cost" and therefore not part of decisions about future expenses. I think he would also say it's because of our societal preference for the glitter of "new" vs. the practicality of "existing," which may not be part of the accounting equation, but certainly humming in the background.
In his talk, Young used his own home to compare the energy recovery periods required to simply perform an energy upgrade to his home, to abandon the home and build a new one in the suburbs, or to demolish and rebuild in place. When he accounted for the embodied energy in the new buildings (whether in place or in the suburbs), the energy to demolish the existing building, and operating energy required for the remodeled or new building, it became clear that the remodel was the best choice when considering true energy performance. In scenarios provided in his book, energy recovery calculations result in recovery periods that exceed "the expected useful lives of many buildings being constructed today." And this is without calculating in the transportation energy expenses that are likely to accrue when the new building is built in a greenfield out in the suburbs.
In the economic realm, Young compared the job creation resulting from highway, new, and rehab construction. In jobs per million dollars spent, rehab wins again. Although a small part of the construction activity (Young estimated 5%), rehab creates roughly 5 more jobs per million dollars spent than highway construction, and 2 more jobs per million dollars spent on new construction. If I am interpreting Young's figures correctly, just by turning our economic recovery lens on rehab and away from highways and new construction we could potentially create between 6-12% more jobs per million dollars spent on construction. (And we might actually reduce the environmental, social, and economic negative impacts of sprawl -- even if it's "green")!
Young's talk introduced some great food for thought, but I'm so glad to be reading his book. In his concluding chapter, "Putting it All Together," he provides a list of "challenges" for stewards of the built environment, ranging from advocating outcome-based codes (since prescriptive codes are based primarily on new construction practices) to presenting project lessons learned (both positive and negative) to "decision makers and policy shapers who mediate building preservation and reuse policies." Lots to work on.
Kathleen O'Brien is a long time advocate for green building and sustainable development since before it was "cool." She lives in a green home, and drives a hybrid when she drives at all. She continues to provide consulting on special projects for O'Brien & Co., the firm she founded over 20 years ago, and provides leadership training and mentoring through her legacy project: The Emerge Leadership Project.