Silverstein Properties announced a plan to renovate and update one of the oldest Class-A office buildings in New York City on Monday.

120 Broadway, also known as the Equitable Building, was built in 1915 as the largest office building in the world and the first with passenger elevators. Silverstein Properties, which purchased the building in 1980, will spend $50M on updates to the entrance, lobby and elevator systems, starting in early 2018.

Architectural firm Beyer Blinder Belle, a tenant of 120 Broadway, will be leading the redesign, which will center around a bronze grille-patterned theme. A combination of grille and glass will replace green marble in the archway above the entrance, allowing considerably more natural light into the lobby. Bronze accents will also adorn the revolving doors, the front desk, new light fixtures and the elevators.

The lobby will also see an updated roster of retail options in the building, as well as a redesign of the staircases leading down to the in-building subway concourse. The concourse, which leads to the Wall Street stop of the 2, 3, 4 and 5 lines and the Broad Street stop of the J and Z lines, will be decorated with new murals. Additional amenities, such as a redesigned roof deck and a bike room, will also be part of the Financial District building's renovation.

After a renovation of the energy systems in 2014 that gave the Equitable Building EnergyStar certification, Silverstein Properties continues to invest in the property to keep pace with new construction in New York, such as the nearby World Trade Center, which Silverstein is also developing. In August, MacMillan Publishing signed a long-term lease to move to 120 Broadway from the Flatiron Building.