Can LEED Survive the Coming Carbon Neutral Age?

1 | 2 | 3 | next>>

Continued - 2 of 3

USGBC’s Horst calls LEED “a leadership tool,” not just a checklist. “It may not dramatically alter a typical project,” he says, “but it requires the design team to go through the ideas and think about what they mean.” Douglas Farr, a Chicago-based green consultant, hopes those discussions move people beyond a small-bore “widget mentality” that focuses on the dollar payback of a fluorescent bulb or a triple-glazed window. Ideally, LEED requires the building team to look for strategies that work together to multiply benefits (better lighting, for example, yields less need for cooling) or that offer tangible advantages that can’t be marked in the ledger as strictly ecological — like the psychic benefits of operable windows.

Owners may also have to make hard choices as they consider LEED’s costs, benefits and inevitable tradeoffs. “If a client has gone public about its intentions to certify to a certain level of LEED, they’re forced to look much harder at ways to cut costs without taking out LEED strategies,” explained Arup’s Cousins. “Is that Italian marble more important than the photovoltaic panels? Do you absolutely need to buy a ton more air conditioning rather than build the rainwater management system?” Reluctance to make these tradeoffs is another reason many owners ask designers to use LEED guidelines but skip the certification process. Architect Bohlin Cywinski Jackson did not seek LEED certification for Seattle’s 2005 Ballard Library, for example. ”We feared that if we promised silver and the bids came in too high there would not be funds for overruns,” senior associate Robert Miller told me after it opened. The building did meet its budget and went on to win many awards that cited its inventive green concepts.

While American architects tend to pick out LEED strategies a la carte, European buildings push large-scale innovation very rapidly into the marketplace. The green features of Foster & Partners’ gold-rated 2006 Hearst Tower are pedestrian compared to the daylighting and natural-ventilation strategies the same architect used in the Commerzbank tower in Frankfurt almost 10 years earlier. The just-opened New York Times tower features an advanced two-layer wall system and sensor-driven light controls. The Times’ design architect, Renzo Piano, did all those things in the 1998 Debis Tower in Berlin. But Debis also harvests the building’s rainwater, draws cooling from an onsite pond, and opens windows for natural ventilation using computer-driven sensors that monitor the weather.

LEED may ask too little, but the extraordinary innovation that comes from Europe flows from cultural norms, energy costs, and tax treatment that allow designers to focus on a much longer time horizon than is common in America. “Europeans expect buildings to last a long time,” explained Arup’s Cousins, making higher upfront investments pay. Highly innovative buildings are considered “the right thing to do” in Europe, she says. In the U.S., “the talk immediately turns to legal risk and money.”

The recent addition of points for innovation may permit LEED to reward more groundbreaking designs. Farr has watched strategies that not long ago were deemed exotic become mainstream. “First you make them legal,” he says, referring to waterless urinals and geothermal heating and cooling systems, which many building codes prohibit. The city of Troy, Mich., may rewrite stormwater management rules and parking-lot construction requirements after Farr and architect Joe Valerio (of Chicago’s Valerio Dewalt Train) convinced officials to reduce parking in favor of native grasses and wildlife-attracting ponds in a new headquarters for the Kresge Foundation. That three-acre prairie absorbs almost every drop of the site’s runoff. Not a big deal, perhaps, but it suggests LEED’s invisible multiplier effect, especially as local governments struggle with flood control and declining water quality.

The wider public appreciation for the threat of global warming has moved LEED into the mainstream. With that acceptance, however, has come a push to focus the program heavily on energy. Kent Peterson, president of the American Society of Heating Refrigerating and Air Conditioning Engineers (ASHRAE), says “we’re pulling out all the stops to move the building industry up the energy-conservation curve.” (ASHRAE writes the national standards that guide building mechanical systems.) The society has partnered with AIA, USGBC, and the Illuminating Engineers Society on design guides that should deliver efficiencies 30 to 50 percent greater than the current code.

ASHRAE also intends to introduce a mandatory standard by 2012 that will require all new buildings to be 30 percent more efficient. This will enforce a stiff learning curve on designers and builders, which may relegate the rest of LEED to the status of frill if coping with energy becomes all-consuming. ASHRAE and AIA are pushing Congress to commit to building construction that is climate neutral by 2030. To meet that standard, ASHRAE will have to get a workable methodology into the market by 2020, says Peterson, a short time for standards that will drive wholesale building-industry transformation.

Advocates of green building have long claimed that LEED structures need not cost more than conventional construction. A recent study, “The Cost of Green Revisited,“ by construction-management consulting firm Davis Langdon, supports the claim — at least up to LEED Gold level. (The study didn’t look at Platinum buildings.) The report did include a caveat: “Few projects attempt to reach higher levels of energy reduction beyond what is required by local ordinances or beyond what can be achieved with a minimum of cost impact.” This suggests that a heavy energy focus by LEED may become a hard sell it it’s perceived as more costly to implement.

Achieving large energy efficiencies inevitably forces designers into so-called integrated design, which is how advanced buildings in Europe and elsewhere deliver great benefits — trading more elaborate walls and windows for fewer electrical and mechanical components. Morphosis’ design for the San Francisco Federal Building, for example, largely replaced air conditioning with adjustable sunshades, natural ventilation, and window walls that harvest daylight. “With integrated design you’ll get 70 percent to the carbon neutral goal,” Peterson explained. “You’ll get the rest by onsite energy generation,” through mini-power plants, wind or solar. But these designs only deliver impressive gains if every element works seamlessly together. It’s a more disciplined approach than choosing from LEED’s checklists.

(Continued)

1 | 2 | 3 | next>>