Pelli Clarke Pelli Architects and Hines have submitted a revised plan to reduce the height of the Transbay Tower in San Francisco, US to 1,070ft from its original plan of 1,200ft.
Under the new plans, the tower would be 60 storeys with an entrance at First and Mission streets adding a 150ft sculptural, transparent metalwork frame to the top of the structure.
The new plan also incorporates 1.35 million ft² of office space, down from 1.8 million, including a residential component and a half-acre public plaza.
Hines senior vice president Paul Paradis said: "San Francisco is ready for more office space, so we want to advance as soon as possible."
The revised design will keep the obelisk structure of the original building with an enclosed space allowing people to see through the crown.
As per the new plans, the skin of the building will be covered by glass with lattice-like metal in the exterior, which would be narrowed to the curved corners to create a soft profile.
The architect says the new skin design will create a vase-like effect, while the corners will provide light at all times, even when there is low visibility during cloudy days.
Pelli Clarke Pelli Architects won an international competition in 2007 to design the tower and the multimodal transit centre at its base, the Transbay Transit Center.
The tower connects directly to the Transbay Transit Center, which will house 11 bay area transit systems.
A 5.4-acre public park that will be the anchor of a new mixed-use neighborhood is planned to be built on top of the Transit Center linking directly to the tower.
Upon completion Transbay Tower will be San Francisco’s tallest tower, overtaking the Transamerica Pyramid, completed in 1972.
Construction of the tower is expected to begin next year with a possible opening in 2016.
Image: The Transbay Transit Center will sit at the base of the tower. Photo: Transbay Transit Center.