World Trade Center leaseholder Larry Silverstein plans to select architects of "international stature'' -- possibly by next month -- to design each of four proposed buildings at Ground Zero, said David Childs, chief architect for the site's 1,776-foot Freedom Tower. The decision may require changes to the designs of Daniel Libeskind, whose master plan was selected in February by the Lower Manhattan Development Corp., Childs said. Libeskind's design has angle-topped buildings of 50 to 65 floors in a semi-circle, starting with the smallest to the south and rising to the Freedom Tower in the northwest corner. "Larry has begun to identify to himself and will announce, I think fairly soon, the architects he'd like to have involved in his other four buildings, which I think will impress people,'' Childs said in an interview. "I mean these are not just your ordinary architects. These are people of great international stature.'' The architects will augment Libeskind, Childs and Spanish architect Santiago Calatrava, who has been chosen to design the site's transportation center. The 16 acres where 2,792 people were killed in the Sept. 11, 2001, terrorist attacks is considered the centerpiece for reviving New York's financial district and helping to boost the city's economy. Libeskind's plan also calls for a memorial, a museum, performing arts center and retail space. Silverstein leased the site from the Port Authority of New York and New Jersey for 99 years six weeks before the towers were destroyed. He is in a court fight with 20 companies that insured the trade center, including lead insurer Swiss Reinsurance Co. Silverstein contends that under New York insurance case law he is entitled to twice his $3.55 billion policy limit on the theory that the crashes of two hijacked jetliners into the twin towers were two separate insurable events. Unlike the Freedom Tower, which New York Governor George Pataki has said he wants started by next August, Silverstein has said the four other office structures won't be built until later in the projected 10-year construction timetable for the site, and then in response to market demand. According to statistics from Trammell Crow Co., a property brokerage, 15.5 percent of office space in lower Manhattan was vacant in the second quarter of this year, compared with the record low of 5 percent in December 2000. The citywide office vacancy was 14.2 percent. Hiring the architects now is "simply more orderly'' because it allows them to "work together on this,'' said Silverstein's spokesman, Gerald McKelvey. Source: Bloomberg