Existing buildings certified under the U.S. Green Building Council’s (USGBC’s) Leadership in Energy and Environmental Design (LEED) green-building rating system are outpacing their newly built counterparts: In December 2011, the square footage of LEED-certified existing buildings surpassed that of LEED-certified new construction by 15 million sq ft on a cumulative basis.

“This new data marks the first time that LEED-certified existing buildings have surpassed LEED-certified new construction cumulatively,” Rick Fedrizzi, president, chief executive officer, and founding chair of the USGBC, said. “The market is becoming increasingly aware of how building owners can get better performance through green operations and maintenance.”

Historically, the stock of LEED-certified projects overwhelmingly has been made up of new construction, both in volume and square footage. That began to change in 2008, when the LEED for Existing Buildings: Operations & Maintenance (O&M) rating system began experiencing explosive growth. In 2009, projects certified under LEED for Existing Buildings: O&M surpassed those certified under LEED for New Construction on an annual basis, a trend that continued in 2010 and 2011.

“The U.S. is home to more than 60 billion sq ft of existing commercial buildings, and we know that most of those buildings are energy guzzlers and water sieves,” Fedrizzi said. “... Making these existing buildings energy- and water-efficient has an enormous positive impact on the building’s cost of operations. And the indoor-air-quality improvements that go with less-toxic cleaning solutions and better filtration create healthier places to live, work, and learn.”

The USGBC is supporting the White House’s Better Buildings Initiative, a plan catalyzing private-sector investment through a series of incentives to upgrade existing commercial and municipal buildings over the next decade.

Citing McGraw-Hill Construction’s Green Outlook 2011 report, the USGBC said that by 2015, the green portion of the largest commercial retrofit and renovation activity will more than triple, increasing to 25 percent to 33 percent of the activity by value, a $14 billion to $18 billion opportunity in major construction projects alone.