Revamped LEED ratings emphasize climate, energy conservation

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The U.S. Green Building Council is remodeling its LEED rating system for buildings, giving greater weight to design elements that reduce energy use and greenhouse gas emissions.

The U.S. Green Building Council is remodeling its LEED rating system for buildings, giving greater weight to design elements that reduce energy use and greenhouse gas emissions.

Member balloting concluded last week on the revised LEED 2009 standard, which incorporates more than eight years of feedback from architects, developers and building materials manufacturers. The Washington-based group's sister Green Building Certification Institute will begin vetting buildings using the revised Leadership in Energy & Design standard next spring.

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Developers and building owners who use LEED 2009 to certify new or remodeled buildings will still earn credit points for recycling construction materials, optimizing indoor air quality and reducing water consumption. However, a full 25 percent of the credits are now geared toward reducing the projects' carbon footprints, up from about 17 percent before, according to USGBC officials convening here this week for the annual Greenbuild conference.

Key changes to LEED include higher baseline requirements for reducing energy use, language that addresses mixed-use projects, and expanded options for using roof materials that reduce the urban heat-island effect. Developers may also earn certification points for building dense, transit-oriented projects with on-site renewable energy.

"Climate and energy efficiency are now the top priority now from a LEED perspective," said Michelle Moore, USGBC's senior vice president for policy and public affairs. "Clearly, with buildings representing about 39 percent of U.S. emissions, putting carbon mitigation first makes sense."

The new 110-point LEED scorecard for new and remodeled buildings nearly doubles the optional credits for energy performance. For example, a new building that is 12 percent more efficient than the American Society of Heating, Refrigeration and Air-Conditioning Engineers' baseline 90.1 energy code gets one credit. A building that is 48 percent more efficient than the baseline code gets 19 points.

Energy-performance credits for renovated buildings are also tiered from 8 percent to 44 percent above ASHRAE code.

Developers that systematically test the energy performance, or "commission," of their buildings will be able to earn two credits instead of one. It is a small but important change, said John Jennings, a manager with BetterBricks, the commercial program of the nonprofit Northwest Energy Efficiency Alliance, which is funded by public and private utilities.

"Commissioning is important to ensure that you actually get the energy savings rather than just hope for them," Jennings explained. "It's an assurance of what you designed into the building."

The remodeled LEED standard also incorporates region-specific credits --- emphasizing heating in the Northeast and water use in the Southeast, for example, explained Brendan Owens, USGBC's vice president for technical development.

The nonprofit USGBC has also created a "bookshelf" of credits that apply to all of its diverse LEED rating standards, which include new construction, existing buildings and commercial interiors.

Taken together, the changes should reduce the time it takes to update the LEED rating systems and certify new projects, Moore promised. About 10 percent of new construction in the United States gets LEED certification, but it typically takes about 90 days to certify a project, Moore explained.

"There is a backlog," Moore added. "The way we've been doing certifications isn't necessarily scalable."

Crafting a green building code

About 1 percent of all buildings in the country are certified under LEED, making it the most widely used green-building rating tool, according to USGBC data. As of last summer, more than 3.5 billion square feet of building projects were registered for voluntary LEED certification.

Washington, Boston, San Francisco and a handful of other cities have begun requiring their largest buildings to attain at least a LEED Silver rating. Meanwhile, USGBC is working with ASHRAE to develop a baseline green-building code that could be applied by any state or municipality.

Dow Chemical Co., which makes Styrofoam insulation, does not implicitly endorse LEED or any other green-building standard. But Rich Wells, the company's vice president for energy, said Dow would support a baseline green-building code as a way to reduce energy consumption.

"The technology is always going to be in front of the building codes, so as technology changes, you have to give [developers] incentives to go beyond the code," explained Wells, whose company published a white paper last week calling on Congress and the White House to improve the energy efficiency of all homes and buildings by 30 percent over the next decade.

Wells and other energy experts underscore that new buildings are not the only solution to reducing energy consumption.

Under LEED 2009, building redevelopers may earn three credits for maintaining 95 percent of the structure's walls, floors and roof. They may earn additional credits for reusing concrete, metal and other materials on-site or recycling them off-site.

The owners of Constitution Center, a former Transportation Department building in Washington, D.C., are pursuing such options to attain a LEED Gold rating, said David Varner, a vice president with SmithGroup, the project's architect.

The 2.1-million-square-foot building's innards and footprint remain largely intact, he noted. More than 75 percent of the construction debris -- about 64 million pounds of concrete and metal -- was diverted from landfills.

Others say even simple energy retrofits, such as swapping out inefficient insulation, windows and light bulbs, are an effective way to make a dent in a building's carbon footprint. More than 40 percent of all energy consumed in the United States goes toward building operations, which include heating, lighting, cooling, hot water and plug-load, noted Ed Mazria, a Santa Fe, N.M.-based architect and head of the climate-change advocacy group Architecture 2030.

"In order to really get a handle on climate change, we have to address building operations," Mazria said.

Earth Policy Institute founder Lester Brown said picking such low-hanging fruit has the potential not only to save energy but also to create new "green-collar" jobs.

Every $1 billion capital investment in energy and efficiency would create approximately 9,500 building-retrofit jobs. Such an investment would also create 1,200 jobs from building and installing solar photovoltaic panels and about 900 wind-energy jobs, Brown estimated.

"In the jobs-creation sweepstakes, retrofitting buildings runs away with it," Brown added. "That's about 10-to-1 over any other investment."