Tall Building News

After yesterday's Insight feature on supertalls now under construction, we couldn't help but set our sights on a few headlines around tall buildings.

First is news that the Blackstone Group, a global investment and advisory firm, is buying the 110-story, 3.8-million-square-foot (350,000-sm) Willis Tower in Chicago for USD$1.3 billion. This amount is about $450 million more than the highest sale for a skyscraper in the Midwestern city (300 N. LaSalle Street, sold last year), and about $460 million more than the tower's current owners paid for the 42-story, SOM-designed building in 2004 when it was known as the Sears Tower. Blackstone is buying a building with a 20% vacancy rate in its office spaces, and they have announced plans to upgrade the tower's retail and observatory spaces, the latter which features the Ledge, glass boxes that project from the tower's 103rd floor.

Second are the results of the London Tall Buildings Survey (PDF link) carried out by New London Architecture (NLA) and GL Hearn. Their data finds 263 tall buildings over 20-stories that are proposed (76), approved (117) or under construction (70) within Greater London. The number of towers proposed and approved increased slightly over the previous year, but those under construction increased by 56%. Most of the 263 towers fall in the 20-to-30-story range, with about 24 of them peaking at or over 50 stories. The study summarizes that "the tall building proposals are predominantly residential as a result of planning, economic and market conditions representing a distinct phase of tower planning in London," generating approximately 14,800 new residences once they are all complete.

Third is a proposal by the London office of NBBJ for a No Shadow Tower next to the Millennium Dome in Greenwich. The design is actually made up of two towers whose concave facades face each other across a public space that becomes the "no shadow zone." NBBJ designed the towers "using a custom algorithm that in part, shapes the form of the building to allow plentiful light in the public spaces outdoors." The below video illustrates how the forms of the towers reflects the sunlight to keep the open space free of shadows.