Developments in Shaky Town
Have developers killed the possibility of higher seismic standards for new high-rises?
By Joe Eskenazi
Published: December 26, 2007 Structural engineer Patrick Buscovich grabs an
oversize metal ruler and stands it upright atop the table like Christopher Columbus
planting a flag on the shore of the New World. Then, unlike Columbus, Buscovich
triggers an earthquake.
He shakes his hand back and forth, unleashing waves up and down the vertical
ruler; its jiggling midsection quickly appears to be in three places at once.
Meanwhile, the top of the ruler sways back and forth, slowly and methodically,
like a metronome atop a piano.
That, Buscovich says, is what will happen to a high-rise condominium when an
earthquake hits. And it will happen: Both high-rises and major quakes are inevitable
parts of San Francisco's future.
"We have never seen really tall buildings go through [a major] earthquake,"
he says. "I'd like to see one or two big buildings go through one so we
can say, 'Boy, we've really got this figured out.' I really wish we were phasing
into this."
That won't happen. On the contrary, San Francisco is going all-out. The massive
skeletons of partially constructed high-rise condos have become a ubiquitous
feature of the city, and many more skyscraper condos are in the works. By now,
the imminent transformation of San Francisco's skyline is an accepted notion
for any curious city dweller. Less well-known, however, is that the city's tallest
downtown skyscrapers are not built to a higher survivability standard than a
bungalow in the Sunset.
At the heart of the thousands of pages of codes and regulations governing construction
is the fact that all buildings are engineered to meet a remarkably straightforward
standard: A structure of two, 10, or 70 stories should "not experience
collapse" in the largest conceivable quake.
At the end of a massive temblor, "If everyone can walk away from the building
safely and the building is completely trashed, that's fine," says Ephraim
Hirsch, a veteran structural engineer and former president of the Building Inspection
Commission. "That's a successful design,"
But is that good enough? While all buildings are held to an equal standard,
not all buildings are equal. As Buscovich notes, a mortally wounded two-story
building is a nuisance mostly to itself, but "a 50-story building is so
big it predominates an entire neighborhood. ... Do we want a higher standard
for that building if it has a problem and affects two whole city blocks?"
Engineers with UC Berkeley's Tall Building Initiative released a study earlier
this year finding that high-rises are inherently more dangerous than shorter
structures in two areas. Windows shattering in a tall building will shower a
larger radius than those falling from a shorter structure. Also, in an emergency,
most high-rise inhabitants must travel a long way to reach an exit.
And yet these problems won't be thoroughly analyzed prior to San Francisco's
entering a high-rise building bonanza. Influential developers have chilled the
discussion of whether San Francisco should improve its standards by threatening
to take their building projects elsewhere if the city were to do so.
Almost universally, the high-rises sprouting in San Francisco use complex computer
modeling techniques to justify building practices that would be forbidden by
the city's traditional building codes. With the longstanding codes regularly
overlooked, UC Berkeley researchers formed the aforementioned Tall Building
Initiative to develop new "design criteria that will ensure safe and usable
buildings following future earthquakes."
One of the initiative's foremost tasks was to determine how the state's builders
felt about constructing high-rises to do more than merely survive the next big
quake. And when its investigators queried local developers about their position
on higher performance standards for tall buildings, the response was blunt and
unambiguous.
The developers — whom the Tall Building Initiative declined to identify
— said if San Francisco adopted exclusive building codes for high-rises,
they'd be inclined to relocate their projects to less discerning cities.
Berkeley professor Jack Moehle, who runs the research center, says that is a
real threat. "There is certainly a lot of muscle the developers want to
flex in this process. No question about it."
Calls to multiple developers about their position were not returned by press
time. The Residential Builders Association of San Francisco also didn't call
back.
But the developers' threats weren't the only obstacle thrown Moehle's way. Shortly
after Isam Hasenin took over the San Francisco Department of Building Inspection
in mid-March, he abruptly pulled the city out of its working partnership with
the Tall Building Initiative. Calls to Hasenin were returned by communications
manager Bill Strong, who said Hasenin's decision to cut ties was strictly financial
— so Moehle's group won't be getting the $250,000 toward its operating
budget it was counting on.
Strong confirmed what others in city government and the building community had
said off the record: Hasenin is an avowed opponent of cities adopting building
codes more stringent than the state's, so he was fundamentally opposed to the
Tall Building Initiative's research into higher performance standards from the
outset.
In fact, the San Francisco Planning and Urban Research Association (SPUR), a
city think tank, is also preparing a paper on seismic standards. Executive director
Gabriel Metcalf acknowledged Hasenin has already advocated against more stringent
building standards with him.
Unsurprisingly, SPUR has also heard from developers. Joe Maffei, a structural
engineer helping to draft the association's forthcoming paper, confirmed that
developers and builders sent "a flurry of e-mails" after higher standards
for tall buildings were even made a topic of debate.
High-rises, in fact, seem to be one of the few subjects Mayor Gavin Newsom and
Supervisor Chris Daly can agree on. The mayor has been an emphatic supporter
of high-rises and gleefully presided over One Rincon Hill's groundbreaking ceremony
in 2005. Daly, meanwhile, gave high-rises his blessing after inducing developers
to donate millions of dollars to charities of his choosing that same year.
With that in mind, William Holmes, an engineer and group leader with the Tall
Building Initiative, holds out little hope the city's elected officials will
alter the status quo any time soon. A move in that direction would "require
a champion or some activist group," he says. Fellow structural engineer
Loring Wyllie adds, "Developers carry a certain amount of clout. They usually
contribute generously to politicians. That's the way our system works."
Maffei is more optimistic, though he notes it may take a good-sized quake to
shake up politicians' priorities. He feels a high-rise condo's safety could
be "rated" and eventually be a major selling point, as is the case
for Volvos. And, since only 20 to 30 percent of a building's price tag is tied
up in material costs, he thinks safety measures calling for additional rebar
or concrete won't alter high-rise budgets much, if at all. He predicts SPUR's
work may find its way into the city's building code — in 10 years.
Of course, by that time the city will be transformed. So while high-rises probably
won't be held to higher seismic standards than their shorter counterparts for
a while — if ever — the good news is they are subjected to far more
scrutiny.
The skyscraper condos currently mushrooming throughout the city underwent peer
reviews by three-engineer panels, a process that can sometimes drag on for years
— often by design. "If a peer review panel seriously thinks there's
an issue of public safety, you can dig in your heels and usually get a change,"
Wyllie says.
The chief source of debate between builders and engineers on the peer-review
panels frequently seems to be money – and often not even much of it. "What
do these high-rise projects cost — a couple hundred million dollars?"
Wyllie says. "Sometimes you're arguing over something that'll make a $100,000
change in a $200 million project." Then his lips curl into a sly grin.
"Of course, if we drag out that peer review two months longer, two months
of capital is going to make that little change seem pretty cheap."
Should a fire break out on the top floors of any of the high-rise condos now
under construction, however, all the hard-nosed peer reviewing in the world
won't mean quite so much to the firefighters trudging up the stairs.
As of Jan. 1, new San Francisco high-rises taller than 200 feet will be mandated
to have fire-resistant elevators designed to transport firefighters to the top
floors. None of the current high-rises has one: Without an elevator specifically
designed to withstand the heat of a towering inferno, ascending a 60-story building
such as One Rincon could take a fully laden firefighter more than two hours.
Fire Marshal Barbara Schultheis pushed hard to get those fire elevators included
in the '08 code — and noted that structures without them cannot easily
install the elevators retroactively. "They've got to be designed into the
building," she says. When asked what the fire department's backup plan
is to fight blazes on the upper floors of high-rises without a fire-resistant
elevator, she could only answer, "Plan B is to fight them like we've always
fought them." In other words, they'll take the stairs. It's hardly comforting,
which is why Schultheis was such an advocate for the elevators in the first
place.
In the realm of earthquake safety, however, virtually every structural engineer
contacted for this story insisted the high-rises are likely among the city's
safest buildings, largely due to the peer reviewing. And yet "safest"
is a relative term in San Francisco. Half of the city's building stock erected
prior to 1980 — built to antiquated codes and using outmoded designs —
will be damaged beyond repair in a major quake, according to Chris Poland, the
structural engineer chairing SPUR's seismic mitigation group. What's more, of
the irreparable buildings, "10 to 15 percent of those are going to collapse,"
he says. "Those will be the buildings people get killed in." With
this kind of catastrophe in mind, he is less worried about a full-scale disaster
from the peer-reviewed, computer-tested new high-rises: "Too many people
are watching them too closely."
And you can count Buscovich in that group — because they're blocking his
view. Bemoaning One Rincon, he confesses, "I don't like that 'finger' in
front of the bridge. But it's there, and soon the remaining skyline will be
filled in."
He continues: "San Francisco has only about 150 years of history. And once
these things are built, we're talking about them being up another 50 or 100
years."
Well ... let's all hope.