The U.S. Treasury Building is located next door to the White House along Pennsylvania Ave. in Washington. (KAREN BLEIER/AFP/GETTY IMAGES)

Department officials will announce Wednesday that its 142-year-old headquarters, located next to the White House, has earned a LEED Gold certification, making it the oldest building in the world to earn the distinction.

The U.S. Green Business Council, which reviews and approves LEED applications, will officially certify the entire building with the ranking during a ceremony Wednesday morning.

Treasury officials said the department spent about $700,000 on LEED-related improvements in recent years, including the installation of low-flow faucets, waterless urinals, lighting sensors and high-efficienty water heaters. Such changes are needed in order for an older building to earn the gold ranking.

“The fact that the home of much our nation’s financial history has achieved this distinction for environmental leadership adds new meaning to the term ‘green’ building,” Assistant Treasury Secretary Dan Tangherlini said in a statement. “We’re proud of the improvements we’ve made around the Treasury Building – both big and small – to help reduce our environmental footprint and save taxpayer dollars.”

LEED (which stands for Leadership in Energy and Environmental Design) is nothing new to the federal government: Current regulations require that all newly constructed or leased federal space must meet LEED standards, as do most other construction projects in Washington. And while a gold ranking is impressive, the most energy-efficient buildings earn a platinum rating.

But considering the age of the Treasury building, and its prime location at 1500 Pennsylvania Ave., the honor is notable.

So are the savings: The renovations mean Treasury is spending $3.5 million less in building costs annually, officials said, adding that the building is using 43 percent less potable water and 7 percent less electricity compared to fiscal 2008.

The Treasury Building (which suffered damage during the earthquake that rocked Washington) was built between 1836 to 1869, making it the third-oldest building in the federal real estate portfolio after the White House and U.S. Capitol. The east and center wings of the building were designed by Robert Mills, who also designed the Washington Monument, according to the Treasury Department.

Staff writer Jonathan O’Connell contributed to this report.

Follow Ed O’Keefe on Twitter: @edatpost

Further reading:

Earthquake damaged U.S. Treasury building

Christine Lagarde: Resolving European debt crisis requires global effort

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