Earlier this fall, the National Academy of Sciences published new data confirming that the Earth’s average surface temperatures now exceeds anything seen since before the last ice age, about 12,000 years ago. Only the most ideological skeptics still question the link between fossil fuel emissions and the current climate warming trend. Fortunately, signs of serious response to the climate crisis have emerged from many sources. California announced in September 2006 that it will reduce its carbon dioxide emissions by 25 percent by the year 2020, and the U.S. Conference of Mayors, representing 238 cities nationwide, made a commitment to reduce the CO2 emissions of their cities by 7 percent from 1990 levels by the year 2012. GE, the seventh largest corporation in the world, announced earlier this year that the company will reduce its emissions by 40 percent from then projected-levels, also by 2012.

The Casey condominiums will reduce energy-related CO2 emissions by more than 55 percent. “We’ve really pushed the sustainability envelope in this building,” says developer Wilde, “and it has helped us see even more possibilities in the future.” Graphic courtesy of GBD Architects.

Members of the design and construction industry have responded as well, and the U.S. Green Building Council’s (USGBC) LEED rating system gives more weight to the energy performance of buildings — closely tied to CO2 emissions and global warming — than to any other section within the standard. Paradoxically, however, some of the very factors that have given LEED a remarkably strong initial market response also may allow the market to become complacent with strategies that, while remarkable compared to conventional practices, are not adequate to avert disaster.

A nice thing about LEED is that it is prescriptive — it offers incremental, measurable performance targets for designers, builders and project teams to achieve. The system is somewhat straightforward and relatively easy to understand. This has enabled LEED to become a highly visible national standard in a few short years; it has been adopted as policy by a number of municipalities, university systems and government agencies, and several states have enacted aggressive tax incentives rewarding LEED certification.

A problem with LEED, however, is that its prescriptive measures are not all fully aligned with true principles of sustainability. The current LEED point structure signals that a building that is 60 percent more energy efficient than conventional practices, or that generates 25 percent of its power on-site with renewable systems, is as good as we can expect. LEED sets targets far above conventional practice, but still short of true sustainability.

a natural step forward

Enlarge this picture Establishing aggressive targets does not mean we will achieve all of them immediately — in many cases the market simply cannot provide the products or systems achieving those goals would require. But, by redefining our expectations, we send a strong signal to our design teams, our customers, and the market, that incremental improvement is not good enough, and that our aim must be to achieve fully sustainable buildings. Only then will we have a real chance to solve urgent global ecological challenges such as biodiversity loss and global warming. Table by Brightworks.

Seeking a more comprehensive view of sustainability, some developers, designers and engineers have turned to The Natural Step (www.naturalstep.org) framework to help redefine their design objectives.

“This is not about incremental improvement,” says Duke Castle of the Oregon Natural Step Network, a leading proponent of systems thinking for sustainability. “True sustainability has absolute limits that must be reached.” Castle points out that using less fossil fuel isn’t good enough: “Sustainability,” he says, “means eliminating their use and moving toward fully renewable, carbon-neutral energy solutions.”

Gerding Edlen Development Company, one of the largest commercial real estate developers on the west coast, has adopted this approach, and is building some of the most sustainable, large commercial buildings anywhere; greatly reducing the use of natural resources and carbon generation, and creating healthier spaces for people to work and live.

For example, the Oregon Health and Sciences University (OHSU) Center for Health and Healing was designed using The Natural Step principles and is outperforming the prescriptive LEED requirements in many areas. The building will dispose of 100 percent of its stormwater onsite and use no potable water for toilet flushing or irrigation. LEED’s point structure stops at 25 percent stormwater reduction and 50 percent reduction in potable water used for sewage conveyance. The 400,000-square-foot OHSU building will surpass the energy code by more than 60 percent and anticipates a LEED Platinum rating later this year. By starting with sustainability and then using LEED as a measure, the building’s developers created a more sustainable building and achieved an outstanding LEED outcome as well.

The Casey, another GED project, also started with an eco-charrette framed around The Natural Step system. The building will use Energy Recovery Ventilators and super-efficient water source heat pumps to achieve energy savings of greater than 55 percent. The building anticipates LEED Platinum certification next year — a threshold not yet achieved in a large residential project.

According to Gerding Edlen Principal Dennis Wilde, in the eco-charrette for The Casey, the development team used The Natural Step framework to help define the sustainability goals and only plugged in the LEED scorecard at the very end of the day. “It is our goal,” says Wilde, “to design buildings that generate more power than they consume and treat more waste than they produce.”

By framing the discussion in terms of sustainability rather than stopping at the prescriptive targets of LEED, Gerding Edlen has redefined their approach to commercial development.

“We’re building state of the art buildings today,” says GED co-founder Mark Edlen. “But state of the art still doesn’t get us to sustainable. My goal for today is to beat code by 50 percent, and within five years, to figure out how to make our buildings net energy producers.”

Using sustainability as a compass has changed the nature of the discussion in the strategy sessions for recent projects. Developers are talking seriously for the first time about climate-neutral buildings, and about eliminating all PVCs and persistent bio-toxins from their buildings. Discussions include sourcing all materials from within a 500-mile radius instead of stopping at the LEED target of 10 or 20 percent. Teams are developing incentives for truckers to bring all the materials to the jobsite using biodiesel in their trucks, and about using renewable power to build buildings, not just operate them.