Disaster Resilience Part of Sustainability, Too
As the world deals with quakes, storms, waves and eruptions, builders realize that surviving and thriving after these threats are key components of sustainability.
As eco-savvy as the earthquake-prone Left Coast might be, it's probably safe to bet that going green won't be the first thing to come to mind when the Big One hits Los Angeles, Seattle, Portland, or San Francisco.
Nevertheless, green-building advocates and disaster planners are finding common ground as they try to convince cost-conscious building owners that keeping a building operational after a punishing quake or other disaster makes economic and environmental sense. Developers and architects already earn green-building kudos for outfitting structures with solar panels and energy-scrimping lighting. Now some builders wonder whether keeping a building standing should earn them similar credit.
“If we're taking a building and putting it on top of an earthquake fault, and if we haven't considered and evaluated the lifecycle performance from those earthquake risks, I don't think we can really call a building sustainable,” says Erik Kneer, an associate engineer who works in the Oakland offices of Degenkolb.
Kneer and colleagues at his San Francisco-based firm, as well as other seismic engineers, are starting to promote the concept of resilience — the ability for a community or structure to survive and quickly recover from a disaster — as essential for green building. Any building, after all, represents tremendous amounts of “embodied energy” from extracting raw materials, transporting them, and ultimately discarding them when a building is no longer usable. What happens if it's destroyed long before its predicted lifespan? All that energy will again need to be expended.
“For green buildings or something that you're calling sustainable, it doesn't make sense to call it sustainable if you haven't evaluated the long-term risks associated with the natural hazards for that building,” Kneer says.
The latest sustainable construction techniques are useless, he adds, if those high-performance systems are placed in a structure that can't withstand conditions like extreme seismic shaking or hurricane force winds.
“To me, that just doesn't make any sense,” he says. “It's like taking a Ferrari engine and putting it in a Yugo.”
While most clients want to know how much money a disaster might cost them, Kneer says a growing interest in corporate social responsibility motivated Degonkolb to create a tool, called Envisa, to measure environmental impacts. Developed by Matthew Comber, Envisa couples information about the long-term environmental impacts of a structure's building materials with federal data about the likelihood of various hazards. The results illustrate both how costly quake damage can be for a range of building systems, and what carbon dioxide emissions would be associated with recovery and reconstruction of a building.
“For a new building project that's going for LEED certification, this provides a quantitative basis to justify decisions on seismic resiliency,” says Kneer.
The certification Kneer refers to — Leadership in Energy and Environmental Design, or LEED — is the widely accepted standard developed by the United States Green Building Council. Kneer, who is LEED certified, sits on the regionalization committee for the USGBC's Northern California chapter. He wants credits for green building to be more closely tied to a project's regional context. Along the Pacific Coast, for example, regionalization credits might be based on a building's seismic performance, while in the Southeast credits might be issued for the ability to withstand hurricanes.
Many regional chapters have advocated for such credits, and chapters can adapt their guidelines somewhat to address regional concerns, but disaster resiliency hasn't made its way into the organization's certification rules.
Still, one project has received LEED credit for its seismic performance. Opened last year, the Ray and Dagmar Dolby Regeneration Medicine Building at the University of California, San Francisco, stands on a base-isolation system designed by San Francisco's Forell/Elsesser engineers. It operates like a car's shock absorber. When the Big One strikes from the nearby San Andreas Fault, the base of the building will shake with the quake, but components separating the lab above will keep most of the energy away and, hopefully, prevent significant damage.
It's not the world's first base-isolation system. What made it unique, says Steve Marusich, the project's lead engineer, was that by building a base that could move the system requires far fewer materials than an unmoving base that would absorb as much energy. Cutting down on building materials also means cutting down on the amount of carbon emissions necessary to extract, transport, and fabricate those materials.
In this case, Marusich says, the moving base meant a 43 percent reduction in carbon emissions related to building materials. In addition to requiring less material, the ability to keep the lab operational and limit the need for repairs after a quake means reducing the impacts (and costs) associated with replacing structures and systems that could have been damaged.
These features earned the new research facility one LEED Innovation and Design point (a building can receive up to four for innovation and design). A newly constructed building needs between 39 and 51 points to earn LEED Gold certification, which in turn can qualify the building for tax incentives and other assistance.
“The sustainability isn't just the structure itself,” Marusich says. “The base isolation protects all the non-structural elements, all the contents of the building.”
No formal LEED resilience points exist, but the building council is starting to pay attention to how green building practices contribute to resilience. In February, the council released a report with the University of Michigan that focused on how green building techniques may help the country withstand the threats expected to accompany increased global temperatures.
Chris Pyke, the building council’s vice president of research, says he thinks there are elements of resiliency to every category of LEED credit. Though resilience won't become a category of its own until at least the next round of LEED revisions — possibly three or more years away — the February report reminds the public that the ability to withstand disasters is worth attention.
“Resilience is another dimension to think about while you are pursuing green building,” Pyke says.
Resilience planning isn't limited to buildings. Many entire communities are integrating sustainable futures into disaster plans, inspired by examples like Greensburg, Kansas, where there has been a particularly verdant recovery after a devastating 2007 tornado.
Jim Schwab, a senior research associate at the American Planning Association and the manager of the APA's Hazards Planning Research Center helped the Federal Emergency Management Agency study post-disaster recovery 15 years ago, and is working on a revision of that agency's disaster plan.
“Just going through the exercise of thinking about what type of opportunities you might seize as a community to rebuild a more resilient, more sustainable, safer community after a disaster occurs speeds up the process after it does happen,” Schwab says.
Degenkolb's Kneer says it's important not to just focus on buildings, but also on infrastructure. Environmental damage can be wrought by sewage spills, broken gas lines, generator use and other urban earthquake damage.
“The end goal isn't just X client's building is resilient,” Kneer says. “The end goal is that we have resilient cities that are up and operational after a seismic event.”