Sky lobby

A sky lobby is an intermediate interchange floor in a skyscraper where people can change from an express elevator that stops only at the sky lobby to a local elevator that stops at a subset of higher floors.

Early uses of the sky lobby include the original Twin Towers of the World Trade Center and 875 North Michigan Avenue (John Hancock Center) in Chicago.^[1]

World Trade Center (Manhattan)

The Twin Towers of the original World Trade Center were among the first buildings to utilize sky lobbies. The 110-story towers had sky lobbies on the 44th and 78th floors, from which four banks of local elevators provided access to other floors, a design inspired by the New York City Subway. The inclusion of sky lobbies resulted in more usable office space on each floor while also rendering construction beyond the 80th floor economically feasible.^[2]

Nearly 200 people were estimated to have been in the 78th floor sky lobby of the South Tower of the original World Trade Center when it was hit directly by United Airlines Flight 175, leaving only around a dozen who survived the impact and escaped the tower before it collapsed.^[3][4]

The present-day One World Trade Center is the tallest skyscraper in New York City. Like the buildings it replaced, the new building has a sky lobby to reduce the amount of space devoted to elevators. The sky lobby is on the 64th floor; each set of five to six stories is served by a separate bank of elevators. The elevators to the sky lobby, along with the ones used for the nonstop service to the 100th-floor One World Observatory, are the fastest in the Western Hemisphere. The observatory elevator transports passengers 100 floors in under one minute.^[5]

875 North Michigan Avenue (Chicago)

The John Hancock Center's sky lobby on the 44th floor serves only the residential portion of the building that occupies 48 floors (floors 45–92). Three express elevators run from the residential lobby on the ground floor to the 44th floor, with all three of the elevators stopping at one of the parking garage levels. At floor 44, residents transfer to two banks of three elevators. One bank serves floors 45–65 (21 floors in total) and the other serves floors 65–92 (28 floors).

The tower's 44th floor sky lobby includes a pool, gym, dry cleaner, convenience store, about 700 mailboxes, two party rooms, a sitting area overlooking Lake Michigan, a small library, a refuse room (with trash chutes emptying here), offices for the managers of the residential condominium,^[6] and a polling station for residents during elections.

Floors above 92 are serviced by direct passenger elevators from the ground floor, and by two freight elevators that serve floors 44–98 (55 floors).

Buildings with sky lobbies

References