CHICAGO – Skyscrapers eventually will be built again in the United States, but should have better safety features such as improved exits and fireproof floors, experts said Monday.
About 24 leaders in architecture, engineering, building security and fire protection who attended an all-day session on the future of tall buildings also discussed integrating power and security systems and building skyscrapers with separate elevators for firefighters.
"Buildings as they exist today are safe. However, in the world in which we live today, we are attempting to evaluate how can we make buildings safer," said Ron Klemencic, chairman of the Pennsylvania-based Council on Tall Buildings and Urban Habitat, which hosted the session.
The Sept. 11 attacks that brought down the World Trade Center will not end skyscraper construction but might slow the process, some architects said.
A. Eugene Kohn, president of the architectural planning firm of Kohn Pedersen Fox in New York City and London, said he doesn't think anyone will propose building a super-tall structure -- between 80 and 100 stories -- in the next 10 years.
Even before the attacks, the slowing economy and decreasing demand for office space already was lessening the demand for tall buildings, said Kohn, who was scheduled to attend the council's meeting but did not.
"Emotionally, you would worry about whether people want to be on the 100th floor," he said during a telephone interview from his London office.
But demand for skyscrapers will return, architects said. Skyscrapers offer ample office space while taking up little land, and create interesting skylines, architects said. They also allow people to live and work near cultural attractions that cities typically offer.
"Until we're ready to give up our way of life, we'll continue to build tall buildings so we can be closer to the things we enjoy," Klemencic said.
Historically, tall buildings have been safe, said William Baker, a structural engineer at Skidmore, Owings & Merrill in Chicago.
"Until people started flying airplanes into buildings, one of the safest places to be was a high-rise building," he said. "People shouldn't extrapolate what happened to the World Trade towers to construction in general."
But when construction resumes, there are ways to make skyscrapers safer, he and other architects said.
In Asia, for example, many of the tall buildings have been built to include refuge floors -- fireproof areas where people can gather below a fire. The floors are also designed to stop fires from spreading through a building. Some Asian skyscrapers also have heavyweight concrete cores and elevators that are reserved only for firefighters, Kohn said.
"We would all need to sit down and examine the advantages to these things," he said.
But even small things can improve building safety, said Adrian Smith, an architect with Skidmore, Owings & Merrill, who attended the council meeting.
For example, flashlights can be provided on each floor, stairwell lighting can be battery-operated to work during a power failure and security at building entrances can be enhanced, he said.
Smith and Baker said the use of elevators for emergency evacuations should be considered as well. That could require designing elevator shafts so that smoke can't get inside, they said.