NEW YORK CITY-Monday Properties’ 230 Park Ave. has been certified LEED Gold for Existing Buildings, reportedly the first prewar office tower in the city to achieve that rating. The certification is in line with the office landlord’s portfolio-wide program of systems upgrades.

In a project that began in 2009, Monday implemented energy management systems that it says will reduce energy costs and equipment use without interfering with tenant operations.  The company also installed energy-efficient lights, thermo-pane windows, extensive load shedding systems and numerous equipment upgrades.

According to Monday, the upgrades reduced energy consumption by an estimated 200 kBtu per square foot and cut back on the landmarked 35-story office property’s carbon emissions by 7,000 tons per year. Additionally, 230 Park’s Energy Usage Index and estimated Greenhouse Gas Emissions are now 30% lower than the national average, the release states. Monday worked with CodeGreen Solutions to develop the initiatives that led to 230 Park’s certification by the US Green Building Council.

Also on Tuesday, the owner of another East Side office tower, TIAA-CREF, said its headquarters at 730 Third Ave. has undergone infrastructure upgrades that will save an estimated $765,000 per year in energy and operating costs. For its installation of a rooftop thermal storage solution and other initiatives, TIAA-CREF is scheduled to receive the Trane “Energy Efficiency Leader in Commercial Real Estate Award” in a ceremony at 730 Third on Wednesday.