SF New Developments

300 Spear Street will contain four buildings, two highrises of 36 (Infinity II, 350 ft. (107 m)) and 41 stories (Infinity I, 400^[1] or 450 ft.^[2] (122 or 137 m)), and two midrises of 8 and 9 floors bounded on three sides by streets; Main St. to the southwest (also separating this complex from 201 Folsom St.), Folsom St. to the northwest and Spear St. to the northeast (one block inland from the Bay). The highrise towers will poke far above the current highrises in between the Embarcadero waterfront and Spear St., making the complex prominent from places like Treasure Island, and offering spectacular views of the Bay, the Bay Bridge, and the Financial District for those who can afford the units. Along with the Millennium Tower and One Rincon Hill to the west and south, respectively, they will create a new highrise neighborhood in the South of Market district.

Design

The original design for 300 Spear was this (towers to the left), designed by San Francisco”s Heller Manus Architects. It featured a garden on top of the midrise towers and all four buildings were connected togeter. The later, a Miami architectural firm, Arquitectonica, came in and resigned the complex to this version. The four buildings of the complex were split apart and the sky gardens were gone. The complex had its color changed to a blue-green color and adapted a simplified concrete structure with a glass curtainwall system. This current design was approved and it is under construction currently.

Construction

Construction started sometime in April, 2005 when a surface parking lot was demolished to make way for the complex. For the massive 5-story underground parking lot and foundation, it took seven months to excavate all the soil needed to constructed the parking lot and foundation. Midway through the long excavation process, since the complex is located over land that was once a harbor, a buried 1818 whaling ship was found just to the south of Spear St.^[3] This discovery delayed the project for a bit as maritime archaeologists flocked to the construction site to dig up the reminants. After the excavating was complete, the foundation was constructed for the 36 story highrise (Main St. Highrise or Infinity II) and midrise (Main St. Midrise) bordering Main St. and a tower crane was erected for the highrise. The elevator core for the highrise was built first and rose above street level sometime in April, 2006. Construction of the underground parking lot under the highrise and midrise started as the elevator core continued to rise. A second, smaller tower crane was erected in June for the midrise tower. A lifting rig was seen on the tower crane on July 16, but it wasn”t until the weekend of July 22-July 23, 2006 that the crane was raised a few stories so construction can continue on the elevator core.^[4] As of August 4, the concrete foundation mat for the Spear St. midrise and highrise seems to be complete. There are wooden forms poking out from the mat, ready to be filled with concrete. Also, in August, the first pieces of dark-green glass curtainwall were delivered and lie on both Folsom St. and the first few floors of the Main St. highrise. One of those glass curtainwall pieces was installed on the Main St. highrise on August 4 and more pieces were installed on August 8. The third tower crane is set to rise soon in mid-August. On Saturday, August 5, 2006, the taller crane was raised again, but this time, it was raised much more than the first lift, so on August 6, the crane towers over the construction site and the concrete core of Infinity I. It is taller than the nearby GAP building. Another shipment of curtainwall pieces arrived on the site on August 8 and a day later, more pieces were placed. The large Main St. crane was significantly raised on the weekend of October 7-October 8 and pokes out of the San Francisco skyline. Currently, the first 21 concrete floors (framework reaches 23-24 stories) of the 36 story highrise and the seventh concrete floor of the midrise has been built. The elevator core for the 36 story highrise reaches around 26 stories high. Curtainwall glass reaches to the 9th storey and interior framing and work (like walls, sprinklers, plumbing, etc.) has taken place on the first few floors. The core is still below the level of the crane after the second lift. A tall mobile crane was erected sometime around August 11 and on August 17, it began construction on the third tower crane. The third tower crane was set up in early September. Though the crane is still shorter the larger first crane, eventually when the Spear St. highrise is complete, it will be the tallest crane of the site. A massive concrete mat pour has allowed the Spear St. buildings to rise.

courtesy Wikipedia