A 730,000-square-foot, first class office and retail tower at 99 High St. in Boston has received Gold-level LEED certification from the U.S. Green Building Council (USGBC).

The building, owned by TIAA-CREF, recently underwent a far reaching capital improvements program. Jones Lang LaSalle is the construction manager, property manager and exclusive leasing agent for 99 High, according to a statement.

"Improving the environmental efficiency of our properties benefits our tenants, investors and the community. We are proud of the work completed with Jones Lang LaSalle and to earn LEED Gold status for 99 High," said Michael Farrell, director of real estate asset management for TIAA-CREF.

To achieve LEED Gold status, a series of projects were initiated to significantly increase energy efficiency. All building systems have been completely updated. Electricity costs decreased 10 percent, and both steam and water/sewer expenses decreased by 8 percent, according to a statement.

Electricity supply was aggressively managed to significantly reduce cost. Other improvements to enhance performance include: common area lighting retrofit, variable frequency drives for air handling units, high rise elevator modernization, cooling tower replacement, air handling unit upgrades and a new gas boiler plant. The replacement of 4,000 windows and façade repair will be completed in 2011. The window project is expected to reduce energy costs by 18 percent.

99 High is currently 85 percent leased. Tenants include: Adams Harkness, FINRA, Marsh & McClennan, Hancock Natural Resources, Murtha Cullina LLP, Chartis and PNC.