California Academy of Sciences by RENZO PIANO!

Green Architecture’s Grand Experiment— Part 1: The Building
Nine years ago the California Academy of Sciences asked: What’s a natural history museum in the 21st century? Its stunning new building is the emphatic answer.
By Karen E. Steen
Posted September 17, 2008
The new California Academy of Sciences, in San Francisco’s Golden Gate Park, is a building of mythic proportions. At 410,000 square feet, it’s expected to be the largest public building ever to attain a LEED Platinum rating. And, with a $488 million price tag, it also represents the largest fund-raising effort for a cultural institution in San Francisco history. How did this low-profile natural history museum and research facility become a half-billion-dollar marquee project by a Pritzker Prize–winning architect, not to mention a landmark in sustainable design?
According to an oft-told origin story, it all started on the roof. In late 1999, architect Renzo Piano visited the site, climbed up on top of the Academy’s former building, and—there amid the canopy of trees—declared that the roof itself needed to be-come an exhibit of the museum. “This was a magic place in the middle of Golden Gate Park,” Piano recalls. “I said, ‘The roof has got to be part of the experience of the building, part of the itinerary.’”
But that was only nine years ago—the blink of an eye in the world of architecture, and even less in the world of science. If you reach further back, there’s another precipitous event—appropriately enough, an event of the natural world. When the Loma Prieta earthquake struck the Bay Area in October of 1989, the venerable museum, which dates back to 1853, sustained severe damage and was forced to close one building and retrofit several others. At first, the Academy had modest hopes: reopen the shuttered building and fix up another, the beloved Steinhart Aquarium. But then the institution decided to turn the lens of scientific inquiry upon itself, and that’s when everything changed.
In 1997 one of the Academy’s own scientists, Patrick Kociolek, became its interim director. A researcher accustomed to approaching problems through data, Kociolek wanted to test the hypothesis that the planned upgrade was really in the museum’s best interests. “I said to the board, ‘Why don’t we step back and, instead of being driven by the facilities, ask ourselves: What’s a natural history museum in the twenty-first century?’” he recalls. “I had no idea this naive question would lead us so far.”
And so the Academy—the only museum in the country to combine a natural history collection with a planetarium and an aquarium in one building—spent a year and a half studying the role of the science museum in contemporary culture. As Kociolek, who recently left the Academy to become the director of the University of Colorado Museum of Natural History, puts it: “How do you take this Victorian-era model and concept and make it relevant?”
First, the museum analyzed 20 years of attendance data and found a dramatic but consistent decrease. Then it crunched more numbers and realized that other science museums across the country were doing even worse. To confirm some suspicions about the state of scientific knowledge in the community, it commissioned a poll with Harris Interactive. As suspected, it showed that while science is a bigger part of our lives than ever before the public’s understanding of it is lower than it was a generation ago.
The bright spot in all this gloomy news came from an unlikely collaborator: Paul Ray, the demographer who helped coin the term “Cultural Creatives.” In 2001 the Academy hired him to study potential visitors to the museum. Ray’s data showed that science, conservation, and education about nature were important values to large groups of people around the country and crossed political, ethnic, and socioeconomical boundaries. In other words, the need and desire for science education were great, but the existing paradigm, the Victorian cabinet of curiosities, was not up to the task.
“The old model of the natural history museum is the search for eternal truths,” Kociolek says, referring to traditional exhibits such as dioramas, which can remain unchanged for generations. “To me, that’s the antithesis of science. Science is not this collection of facts that you put on a wall. It’s a very dynamic process. It’s about new hypotheses, new data.” Whereas the old science had been about a lone researcher bent over his microscope, the new science was about teams collaborating to solve problems. “At the old Academy, the two most distant points were scientists’ offices,” Kociolek says. “The old physical plan had pushed the intellectual capital apart at a time when the program was calling for bringing the intellectual capital together.”
With so many imperatives to address, it became clear that the Academy would have to do more than just fix up two buildings. The old museum wasn’t going to support the new ideals—and it wasn’t going to survive a continued attendance slump, either. Inspired by Mario Botta’s then-new San Francisco Museum of Modern Art and the de Young Museum’s decision to hire the high-profile firm Herzog & de Meuron, the Academy’s trustees realized they didn’t just need a new building; they needed a forward-thinking design that could carry the whole institution into the new century.
To find the architect who could meet this challenge, the Academy hired Bill Lacy, at the time the executive director of the jury for the Pritzker Architecture Prize. Lacy said he thought there were only about 40 firms in the world who could take on the scale of the project, so the Academy sent out a request for portfolios and narrowed the field of 38 respondents down to six: Toyo Ito, Moshe Safdie, Norman Foster, Richard Rogers, James Polshek, and Renzo Piano. The selection committee brought the architects to the museum site in Golden Gate Park, traveled abroad to see their many built projects, and, in late 1999, invited each of them to an interview.
The first five architects to meet with the Academy all gave the kind of polished presentations you might expect. One arrived with two slide projectors, 50 poster boards, and five staffers, “literally and figuratively surrounding the committee with an answer,” as Kociolek puts it. But the final architect to interview, Renzo Piano, arrived with one associate—his daughter, Lia—and took just ten minutes to set up. When the committee members entered the room, they were surprised to see that he had no presentation materials with him. He had used the ten minutes to pull a table from the corner and rearrange all the chairs into a circle around it. Piano told them that he didn’t know how he would design a new California Academy of Sciences. He would need to hear from them before he could answer that question. “If you go into a meeting and you already know everything,” Piano says, “you lose the capacity to understand.”
As the committee members spoke, Piano sketched ideas. He says one of the most important things he heard that day was another origin story. In 1906 the original museum on Market Street was destroyed in San Francisco’s first big earthquake, and for a few years the Academy’s research ship, a schooner that had just returned from the Galápagos Islands, acted as its home base. “The place that you use for research is the same place you invite people to come and enjoy and discover,” Piano says with obvious admiration. The message he took from this story was that the Academy wanted to find new ways of bringing its scientists and the public back together. The other idea that came through was about building sustainably, he says. “We all thought, This thing has got to be a kind of experiment, a kind of proof that you can be wise in making a building.”
After the interviews, Kociolek says, a number of the trustees wanted to hire the architect who had done the elaborate presentation. But one board member offered a different view. “She said, ‘Do you want to have a lecture from that person, or do you want to have a dialogue with Renzo Piano? That person already told us the answer. Renzo Piano is waiting to talk to us about an answer.’” Her question changed the tenor of the deliberations, he says, and led the board to choose Piano to design the new museum.
One factor in the background during this decision-making process was the de Young Museum, just across the road from the Academy. The de Young had recently unveiled its architectural plans, and a public furor erupted over Herzog & de Meuron’s bold design, which some San Franciscans considered an intrusion into the park. Kociolek says that Piano’s collaborative approach and his experience designing projects within natural settings—like the Beyeler Museum, near Basel, and the Menil Collection, in Houston—seemed to promise not only a sensitive design but also a peaceful public process.
Which brings us back to the roof. Once he was selected, the first thing Piano knew was that he wanted the new roof to be the same height as the one he’d stood on top of: 36 feet. It was an appropriate scale for the park yet tall enough to offer a view, and it retained a vestigial memory of the old building, a local landmark. It was only later, when he learned that some program features—the planetarium and the rain-forest exhibit, for example—would need to be taller, that Piano developed the rooftop’s signature hills. “The idea was: keep the roof at thirty-six feet, and every time you need more, just wave up,” he says. “It’s a landscape that witnesses what is underneath it.”
The other big idea behind the roof—that it should be a habitat for native California plants, birds, and insects—developed more slowly, as Piano’s team worked with botanists from the museum. The planted roof is not just a wildlife corridor; it also insulates the building, reducing energy consumption, and absorbs 98 percent of storm-water runoff. Meanwhile, Piano’s “waves” mean that most of the building doesn’t need air-conditioning: cool air from outside flows down the hills and into the building’s central piazza, while hot air on the exhibit floor rises, hugging the planetarium and rain forest, and is released through automated skylights in the hills.
The building’s sustainable features are so deeply embedded in its design that it’s hard to tell where the aesthetic concept ends and the green design begins. Ironically, Piano was not known as a green architect at the time of his selection. Late in the design process, when the Academy hired the Rocky Mountain Institute to find out how much the green features would cost, it found out that Piano’s design was just two points away from a LEED Platinum rating. Neither Piano nor the Academy had heard much about the U.S. Green Building Council’s LEED program. They had worked not from a checklist but from a total dedication to the value of sustainability to the Academy’s mission. “We decided that we would look everywhere to be green,” Kociolek says. “Whether it was the planetarium, the aquarium, or the office furniture. There were no sacred cows.”
This attitude—that even in a 155-year-old scientific institution nothing is sacred—may be what has allowed the Academy to make its great leap so gracefully. The old museum was made up of 11 separate buildings constructed during different eras. Now, one building integrates everything that the Academy is and does. The aquarium, planetarium, and natural history museum are no longer separate silos—there are live penguins alongside the dioramas and a coral reef surrounding the planetarium. A working lab with floor-to-ceiling windows reveals the research process to the public; scientists will even come out from behind the glass occasionally to present their work to groups of museumgoers. And, whether they are walking the exhibit floor or enjoying the view from the roof’s observation deck, visitors can see and experience the park around them, reminding them—should they need reminding—of that great, green natural-science exhibit outside the Academy’s walls.
Part 2: The Green Roof
The California Academy of Sciences balances a commitment to biodiversity with a demand for beauty.
By Belinda Lanks
Posted September 17, 2008
How does a landscape architect cultivate nature without corrupting it? The question goes back at least to the 18th century, when the novelist Samuel Richardson wrote that the ideal was for the artist “not to level hills, or to force and distort nature; but to help it, as he finds it, without letting art be seen in his works, where he can possibly avoid it.” The undulating green roof that sits atop the new California Academy of Sciences building in San Francisco’s Golden Gate Park tries to strike a similar balance. Like the museum it shelters, it is designed to respect the natural world even as it appropriates it, serving at once as a wildlife habitat and a first-rate work of art.
When the roof (along with the building) opens to the public this month, it will be, at 2.5 acres, the largest such “living” structure in California. Conceived in 1999 by the architect Renzo Piano (who also designed the building), it was completed over six years by a team of specialists that included the environmental consultants Rana Creek; Frank Almeda, a botanist at the Academy; and the landscape-architecture firm SWA Group. The roof has seven signature hills, created to evoke San Francisco’s topography, and is blanketed with nine native plant species, which were chosen for their ability to attract pollinating creatures like bumblebees and hummingbirds, and butterflies such as the threatened Bay checkerspot. Like other green roofs, this one helps regulate temperature indoors and out—though the urban-heat-island effect isn’t a dire concern in San Francisco, where the mean annual temperature is about 58 degrees Fahrenheit. The roof is also designed to absorb 98 percent of all storm water, a decided benefit in a city where the sewage system is often overwhelmed during heavy downpours.
When Piano presented his first sketches to the Academy, he described his idea for the roof by asking his audience to imagine a huge elevated swath of the park, with the museum tucked underneath it. Executing the concept, however, wasn’t easy. One of Piano’s first demands was for an assortment of plant species with a particular kind of look: “He wanted it to be very monolithic, very neat and clean and green,” says John Loomis, of the SWA Group. But the plants that look good together and the plants that thrive together are not always one and the same. So Paul Kephart, of Rana Creek, experimented with 29 different plants before hitting on a selection that would promote biodiversity as well as meet Piano’s aesthetic requirements. “I wanted as much diversity as possible, and I challenged Renzo on this,” Kephart says. “He said, ‘Paul, this is all very interesting, but it has to be beautiful.’” After a few “spirited discussions,” the team chose four perennials and five colorful annuals that live well together, are low-growing (and thus “clean-looking”), and have extensive green periods.
A further challenge surfaced when Piano explained that he wanted to transport and install the plants without using petroleum-based plastic containers. Kephart responded by creating an innovative tray (soon to be patented) from coconut-husk fiber, a waste product from coconut trees. This BioTray is held together with natural latex and lined with 36 strains of fungi, which supply nutrients to the plants. Laid in large numbers on the roof like tiles, the trays degrade within three years, leaving behind a colorful carpet of vegetation.
Piano’s grandest design gesture, the seven hills, also posed an obstacle: How to keep the soil from slipping down them? After an initial solution involving concentric circles was rejected by Piano’s office on visual grounds, the landscape designers devised a drainage system using a 24-by-24-foot grid of rock-filled wire baskets called gabions. In addition to allowing for drainage and strapping the soil in place, the gabions can be used as footpaths for the maintenance crews that traverse the garden’s steep slopes.
Today the roof is essentially complete. But, as with any living system, it will continue to evolve in unpredictable ways. “One of the most fascinating questions I get is, ‘What will this roof look like in five years?’” Almeda says. “People are always astounded when I say, ‘I’d like to be able to tell you, but I can’t.’” Like animals, plant species compete with each other for common resources, and it is not easy to predict which ones will win out. There has already been an unforeseen explosion of growth as birds and bees have dispersed foreign pollen and seeds on the site. “Wildlife will bring things to you that you may not want,” Almeda says. “And, if they bring a native species, just because it’s native doesn’t mean that we will keep it on the roof.” A few water-sucking willows, for instance, were evicted. “If we left them, they’d take the water from everything else and nothing would survive,” Almeda says. A noninvasive monkey flower, on the other hand, was allowed to stay.
The roof will also serve as an outdoor laboratory where scientists and students will study nature in action. Almeda recently made a scientific discovery of his own. Curious about the appearance of a cluster of mushrooms he found on the roof, he sent a sample to a specialist at San Francisco State University. As Almeda recalls, “He said, ‘Frank, I’ve never seen this mushroom anywhere in North America! It’s actually native to Europe, and I’d like to keep it to try to learn more about it!’” At a time when news concerning the environment is grim, that’s an encouraging symbol. “The Academy,” Kephart says, “is essentially a promise that we can restore biodiversity within the urban world.”
Green Architecture’s Grand Experiment
Part 1: The Building
Part 2: The Green Roof
Part 3: The Engineering
Part 3: The Engineering
Weighing the needs of the Academy against the building’s dramatic expression—seven rolling, seismically secured hills—required the work of 320 engineers.
By Michael Silverberg
Posted September 17, 2008
Sitting in a darkened conference room at Arup’s San Francisco office on Market Street, Peter Lassetter flips through a book of early engineering sketches for the California Academy of Sciences. Lassetter, a principal at the firm and the project director for engineering services of the building, pauses on a drawing from 2001, when the design was still very much in flux. Across the rough sketch is written an annotation in clear printed letters: “Crazy! Don’t do it!” That engineer’s plea may well have been heeded—Lassetter couldn’t quite make out from the drawing what was being warned against—but Arup certainly toyed with its share of crazy ideas while working on the Academy, which demanded a team of 320 people (drawn from its London, San Francisco, Sydney, and Hong Kong offices, among others) and included the structural, mechanical, and facade engineering; sustainability consulting; and lighting design. Many of those ideas, in fact, ended up forming the sustainable backbone of the Academy, the features that transformed it from a very green museum into a living, breathing one.
The breath of the museum is both literal and metaphorical: its lungs can be found in the contoured two-and-a-half-acre green roof (the Academy calls it a “living roof”) that is not only the building’s signature gesture, but also the key to its energy-efficient design. The two largest hills rise 27 feet above the roof line as they follow the outlines of the spherical planetarium and artificial rain forest below; the other five slopes weren’t designed with a programmatic purpose in mind. (According to the museum’s press department, they are meant to evoke San Francisco’s quasi-mythical seven hills. As an alternate explanation, Lassetter deadpans, “There’s no truth to the fact that Renzo’s from Italy and there are seven hills in Rome.”)
But Alistair Guthrie, a director of Arup and a mechanical engineer, devised a way to use the hilly topography to turn the roof into what Jean Rogers, a sustainability consultant at Arup, calls an “organ regulating the building’s metabolic processes.” A gap of four feet was left between the tops of the two spheres and the roof, creating what’s known as a stack effect: the narrowing space acts as a chimney, rapidly drawing out warm air through a series of skylights. At the same time, cool air enters the space through ground-level vents and doors, and a westerly breeze across the roof sucks more heat out. Computer-controlled actuators operate banks of 4,000 windows, opening and closing them as needed throughout the day. “As the building breathes, they will move,” Lassetter says.
The scheme ideally suits San Francisco, where high summer temperatures average in the 60s. Even with a glass facade, about 40 percent of the Academy is naturally ventilated, and 90 percent of regularly occupied spaces have daylight. “Museums are very, very highly conditioned spaces, both because of the loads of visitors, and also because of the collections that they’re trying to protect,” Rogers says. “So this idea of having a mixed mode of ventilation—collections that are protected but public spaces that are naturally ventilated and open and breathing, and in existence with the outside environment—it’s very, very unusual. Renzo was probably still thinking of it as a glass box with a green roof.”
The grand idea for the museum might have been settled on, but engineering a wildly rolling roof that could support 1.7 million plants in a half foot of water-saturated soil—and be porous enough to allow for light and air to pass through—was a long and difficult process. Just determining the number, size, and placement of the skylights above the rain-forest and coral-reef exhibitions took months of computer modeling. “People wanted to maximize the number of louvers in the sides of the skylights, but then there were structural engineers that didn’t want those big holes in the roof diaphragm,” Lassetter says. “And these spaces are all naturally ventilated, so we didn’t want lots of glass letting the sunlight in and, therefore, the solar gain upsetting it.”
One of the main challenges throughout the project was balancing green architecture with the needs of a research institution and museum whose collection of 20 million specimens demands strict regulation. Sometimes those goals were complementary. If you compare a glass of water from one of its fish tanks with a sample from a conventional aquarium, you’ll find a lot more stuff floating in the Academy’s. That’s because most aquariums want their tanks to be perfectly clear under the bright lights trained on them. For the Academy, Arup designed the lights to be more diffuse and farther away, allowing for much higher particle content in the water. “That saves a lot of energy on recirculating water because it doesn’t have to be kept gin clear,” Rogers says. “And it’s so much healthier for the fish—that’s what it’s all about.”
But elsewhere the profusion of artificial environments required elements—banks of metal-halide lamps cooking the coral reef, for example—that in a green building are like Texas oilmen crashing a Sierra Club meeting. Which is why it’s all the more impressive that the Academy stands to achieve a LEED Platinum rating. There is a litany of reasons why. All of the structural steel used in the museum is recycled; parts of the old building became a freeway in the East Bay. Sand excavated during construction restored nearby dunes. Fourteen miles of polyethylene piping run under the floors, giving the museum another means to regulate its environment and reducing energy use by as much as ten percent; a perimeter canopy of photovoltaic cells (which Piano actually wanted to be green in hue before Arup convinced him that a drabber color would be more efficient) provides at least five percent of the building’s power. And, while the natural ventilation in the exhibit hall makes it comfortable, Arup didn’t try to micromanage the temperature, relying on a bit of pop psychology to overcome modest fluctuations. “Because it’s such a transparent building, you’re always aware of what it’s like outside,” Lassetter says. “So people are actually a lot more forgiving—if it’s cold and nasty outside, they keep their pullover on, and they do it automatically. They can actually tolerate colder and warmer temperatures if they have that connection to the outdoors.”
Even the structural engineering reflected Arup’s holistic approach. Since earthquakes represent an existential threat to the institution—it has been effectively destroyed by them twice, first in 1906 and again in 1989—great care was taken to protect against the nearby San Andreas Fault. (One of the highlights of the old Academy was an earthquake-simulation exhibit, a raised platform that mimicked the queasy rolling of a major temblor, accompanied by scripted video of flimsy homes collapsing and a cook dropping a huge pot of boiling water. Sadly, it won’t reappear in the new building.) The four corner concrete structures—African Hall, two office-and-research buildings, and a pavilion holding the restaurant and gift shop—are independent buildings with shear walls that, in a big earthquake, will rock back and forth as much as three-quarters of an inch in their foundations.
The way the engineers kept the whole thing safely in one piece was by binding the four buildings with the roof. Each one acts as a sort of table leg to which the roof attaches as a tabletop. “It’s a great way of dissipating seismic forces, because to pick an entire building up takes a lot of energy,” Lassetter says. “If you hold it down rigidly, you’re using brute force to resist the earthquake.” There’s a neat resonance here with Arup’s sustainability work on the Academy: instead of letting the buildings succeed or fail on their own, the engineers hung them all together.
Making a building come alive is a tricky thing, especially in one with so many (actual) balls in the air. There is the danger of stitching together too many gadgets without giving enough thought to the whole. The roof somehow synthesizes the building’s green attributes almost effortlessly. “It could have ended up being a real Frankenstein,” Rogers says, “trying to do energy production and daylighting and natural ventilation and a green roof all in one—but when you’re up there, you’re like, It’s the way it should be. It just fits with the Academy’s program and the park, and yet if you had to sit down and design something that did all those things, it could be awful.”