Although not small by any standards -- built on Port Authority land, it was exempt from zoning regulations and could occupy the whole trapezoidal plot with no setbacks -- the building's floor space and height of 160 m were obviously dwarfed by its older twin brothers
In front of the building, on the WTC compound plaza level, stood Alexander Calder's 8-meter steel sculpture Three Red Wings as well as pedestrian bridges over Vesey Street from the WTC compound, with a round plexiglass tube covering the eastern one.
As the existing foundations through the substation building were mostly not aligned with the perimeter colonnade of the new tower, they had to be fitted with concrete caps to allow transfer of loads to the foundations.
The building collapsed during the terrorist attack on the WTC in September 2001, having been structurally weakened by the destruction of the nearby WTC towers.
Having existed for less than 14 years, the building had one of the shortest lifespans of a skyscraper in history.
For the core, the loads were transferred through a heavily braced foundation slab. 50 new foundation "caissons" were built, most of which had to be squeezed through the substation building.
The building's appearance and its alternating facing -- horizontal glass striping on the Barclay and Vesey Street sides and red granite, holed by smaller windows, on the other two -- set it apart also visually from the Twin Towers of the late 1960s.
Although a part of the WTC in name, the building was on a separate ground lease and tax lot from the rest of the Center. 7 WTC was built atop the power substation building that supplied much of Downtown Manhattan with electricity.