Benjamin Franklin wrote, “When the well is dry, we learn the worth of water.” Although these words were inscribed more than 260 years ago, they now are starting to shape the way green-building professionals around the world design and build. In many places, the threat of depleted utilities and raw materials is no longer considered akin to the fictional plot of a summer box-office drama. Unfortunately, there are cities, states and countries that already have experienced this life lesson firsthand.
However, rather than wait for the proverbial well to run dry, conservation and innovation in the building industry are proving to raise awareness and alter this course. The Living Building Challenge, a rigorous standard by the Pacific Northwest’s Cascadia Region Green Building Council, is providing direction to accelerate such change and pursue sustainability in the built environment.
Credit: Jamie Myers Forsythe
Oregon Health and Science University Center for Health and Healing, Portland
REDUCE, REUSE, RECYCLE
The Living Building Challenge is a framework for projects to reduce their footprints to the maximum extent possible today. Sixteen requirements identify the ideal parameters for building performance and create a basis for dialogue between the various individuals who collaborate on a project. To illustrate this idea, the challenge parallels the nature of a building with that of a flower rooted in place. It impels: “Imagine a building informed by its ecoregion’s characteristics—that generates all of its own energy with renewable resources, captures and treats all of its water, and operates efficiently and for maximum beauty.”
In addition to the usual categories found in most building rating systems, such as site, energy, materials, water and IAQ, the Living Building Challenge also includes requirements for beauty and inspiration. To successfully create a living building, the requirements in all categories, deemed petals, must be achieved.
The Living Building Challenge mandates that a project must achieve at least a net-zero impact over the course of a year for energy and water, using decentralized means. Though stringent, there are completed projects today that strive to meet these goals. In Portland, the Oregon Health and Science University Center for Health and Healing demonstrates the potential is real.
OHSU CHH is a 16-story medical facility, complete with a wellness center, clinical spaces, research laboratories and educational areas. Yet despite this complex program, 73 percent of the building’s total water demand is sourced on-site. The project team achieved this by diminishing the use of potable water from the city’s utility for non-potable needs, such as irrigation, toilet flushing and mechanical equipment. Instead, three different strategies deliver water to these services: a membrane bioreactor with system capabilities to filter and treat wastewater generated on-site; rainwater catchment; and groundwater from adjacent soils to augment supply during dry summer months. The preponderance of potable water brought to the building is used for sinks, faucets, showers and drinking fountains, which is required by state health-department regulations. Analogous to the considerations for any project pursuing the Living Building Challenge, the OHSU CHH team first evaluated the property’s ecological footprint and the context for building. Prior to design and specifications, the team researched microclimate and water flows, identifying opportunities for demand reduction, harvesting and reclamation—a clear parallel to the well-known resource mantra: reduce, reuse, recycle.
The results are measurable. OHSU CHH uses 61 percent less potable water than a conventionally built structure of similar size and location. In addition, approximately 15,000 gallons (56781 L) of wastewater are diverted from the city sewer and recirculated in the building every day; this is equivalent to more than 5 million gallons (19 million L) each year. The significance of this feat is particularly relevant when considering the amount of water drawn by buildings nationwide. According to the Reston, Va.-based U.S. Geological Survey’s last published report in 1995, U.S. commercial- and residential-building operation accounted for 15 trillion gallons (57 trillion L) of water annually, which is 12.2 percent of all domestic potable water.
Credit: Courtesy of Interface Engineering
OHSU CHH water system
Another key to success for OHSU CHH was integrated design. The process not only fostered an aggressive solution for responsible water use, it also led to other features that contribute to the ongoing performance of the building. For example, the energy equation was tackled using passive and active techniques, ranging from building orientation and envelope to photovoltaics and a central utility plant, enabling increased efficiencies and heat recovery. When determining facility placement, the team looked outside property lines; OHSU CHH is located on a reconditioned industrial site tied to Portland’s mass-transit network, relieving the dependence on automobiles and adding public programs at the ground floor desirable to pedestrians and neighboring developments.
During design and construction, it is easy to overlook the significant role that the future occupants will play in the success or failure of a building. Often during these phases, information about the occupant is relegated to program square footage and code requirements. However, it is only when people inhabit the building that it has purpose. This is why the Living Building Challenge requires that all projects be occupied for at least 12 consecutive months prior to certification. The challenge is based on actual, rather than projected, data because even best intentions are inherently speculative.
Credit: Jamie Myers Forsythe
Further, it is impossible for the project team to know precisely how occupants will engage the building: use patterns will ultimately dictate constraints. OHSU CHH demonstrated the CIRCLE NO. 56 or www.eco-structure.hotims.com desire to have the building respond to need rather than be a static entity through the continued tuning of the membrane bioreactor: several months after occupancy, when it was discovered that actual water use and wastewater generated exceeded expectations, the capacity of the bioreactor was expanded.
Bridging the gap between people and buildings is one of the rich outgrowths of the Living Building Challenge. As natural resources continue to dwindle, the presumption that buildings should aim for self-sufficiency is inevitable. It has taken more than two-and-a-half centuries to heed the words of Benjamin Franklin; the planet cannot afford us any more time to act. Step up to the challenge.
Eden Brukman is a co-research director for the Cascadia Region Green Building Council’s Living Building Challenge. She can be reached email@example.com or (503) 228-5533. Thor Peterson, co-research director, can be reached firstname.lastname@example.org or (206) 223-2028.