For four decades, the Los Angeles skyline has been shaped by one rule: Every tall building must have an emergency helicopter landing pad on its roof.
As a result, downtown became a thicket of flat-topped skyscrapers, to the chagrin of architects who yearned to imitate or outdo the pointed spires and slanted roofs of skylines around the world. Other big cities had no such regulation.
And now, neither does Los Angeles.
On Monday, city leaders heralded a code change that allows builders to forego the helipads so long as they put in extra safety features. The change, they say, could remake that boxy skyline, unshackle architects and elevate the look of Los Angeles' cityscape.
"Anyone who's been to New York or cities like Shanghai, Hong Kong and even San Francisco can see how the tops of buildings can help to define the identity of a city," said Michael Woo, a former city councilman who is now dean of the College of Environmental Design at Cal Poly Pomona. "But for Los Angeles, for years, we have limited ourselves."
Downtown's skyline includes some historic landmark buildings with distinctive tops, such as the Art Deco pyramid on City Hall and the ornate clock tower of the Eastern Columbia building. But they have been dwarfed by much taller buildings, notably along Bunker Hill, with boxy flat roofs.
By contrast, skyscraper design in other cities has become increasingly exotic. There's the Shard in London, with its glassy pyramidal tower, the staggered, spiraling heights of the Burj Khalifa in Dubai and the eye-catching crescent shape of the Bow in Calgary, Canada.
Mayor Eric Garcetti called the new rules "a sea change for Los Angeles design." Under the revised regulation, builders will be able to craft skyscrapers that don't have a rooftop helicopter pad if they include other safety features, such as extra set of exit stairs or a dedicated fire service elevator for firefighters to swiftly reach a blaze, automatic sprinklers that activate more quickly in a fire and a video surveillance system.
In a shift from years past, fire officials have embraced the newly revised regulation, saying that new skyscrapers here will be the safest in the country. The fire marshal has already approved changes to the fire code, now in effect.
Garcetti announced the change Monday alongside other city officials from the dizzyingly high, 32-story rooftop of the AT&T Center downtown. Paul Keller, founding principal and chief executive of development company Mack Urban, said he was planning to build spires on three tall buildings at a downtown residential development underway just to the west in South Park.
Los Angeles' requirement for helipads atop buildings more than 75 feet tall was meant to allow airlifts in the event of a fire, attack or other emergency. Fire Department officials said the rules were adopted in 1974 in reaction to a devastating blaze in Brazil, where many victims fled to the roof and waved frantically at helicopters that were initially unable to land. A number of new high-rises were planned in Los Angeles at the time, Fire Department spokesman Peter Sanders said.
But with new technology and design, the restriction became outdated, "one more stupid rule in Los Angeles," Garcetti said Monday.
Fire Department officials said they knew of only one rooftop rescue in a Los Angeles fire in recent decades — a 1988 evacuation from the 62-story First Interstate Bank building (now known as the Aon Center). Helicopters plucked several people to safety. At the time, Deputy Fire Chief Don Anthony said that "if we had had hundreds of people on the roof, they could have effected a tremendous number of rescues," according to the Fire Department archive.
The National Fire Protection Assn. has no position on whether tall buildings should have helipads, said Ken Willette, manager of its public fire protection division. Making sure that buildings are designed to block the spread of fire and allow people to exit quickly through protected routes is "a better defense than relying on a helipad," he said.
The association website notes that rooftop rescue is "an extraordinarily dangerous procedure," partly because heat from a fire can move helicopters up or down, making them hard to control. Author James Chiles, who wrote a book about the history of helicopters, called requiring rooftop helipads "an artifact of an earlier time" before sprinkler systems became common.
Rooftop rescues are so rare, Chiles said, "that money would be better put in a very strong sprinkler system" and fire-protected areas on each floor.
Fire Department officials also cited analysis done in the aftermath of the Sept. 11 attacks, which found that if the World Trade Center rooftops had been accessible, helicopters couldn't have landed because of the heat and smoke. Even if they could, "only a very small fraction of the large number of people trapped" could have been rescued in time, the National Institute of Standards and Technology report found.
Seven years ago, Woo sought to change the rooftop rules while serving as a planning commissioner under Mayor Antonio Villaraigosa. The effort went nowhere, he said, with Fire Department officials saying that the move would pose a threat to public safety. In an interview four years ago with Curbed LA, one Fire Department official compared them to air bags in cars. Since then, Fire Department Chief Ralph Terrazas said the department had undergone a cultural shift.
"Our Fire Department culture is resistant to change sometimes," Terrazas said Monday. "This just made absolute sense to do this."
The changes were born out of a working group convened by the mayor with City Councilman Jose Huizar, Fire Department and building department officials and others. Huizar said that under the revised rules, Los Angeles buildings would no longer be "stuck in the past."
Huizar had previously pushed for alternative rules that allowed a modified helicopter landing space for the New Wilshire Grand building, which is still under construction. Now builders will have the option of not including a helipad on their rooftop if they meet other safety requirements. The new rules apply to all buildings rising more than 75 feet, with stricter requirements imposed on the tallest structures.
Huizar aides said freeing architects to craft rooftop spires and slopes could soon change the look of downtown, with dozens of downtown skyscrapers already under construction or making their way through the permitting process.
"All it takes is one or two iconic, innovative structures and all of a sudden, wow, it becomes a signature," said Will Wright, director of government affairs at the Los Angeles chapter of the American Institute of Architects. Even a small change can have a lasting effect on the city, he added, offering up one famous example.
"What if, 100 years ago, no one was allowed to build the Hollywood sign?" Wright said.
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Times staff writer David Zahniser contributed to this report.