When Italian architect Renzo Piano first came onboard to design the new CAS, he spent hours sitting on the steps of the de Young Museum, looking at the natural landscape. He decided the new academy should look like the landscape had been lifted up, a museum had been placed underneath, and the earth was then laid back on top of the structure—hence, the living roof.
The 2.5-acre garden, created by local living architecture firm Rana Creek, is planted with nine plant species native to San Francisco (since they are able to capture more rainwater than non-native plants and the academy’s green roof is expected to absorb over 3.6 million gallons—or nearly 98 percent—of rainwater each year.) The 1.7 million individual plants were given their roots in over 50,000 biodegradable coconut husk trays, made from the waste products from coconut plants in the Philippines.
Piano wanted the building to maintain a low profile but with two 90-foot domes below (housing the living rainforest and Morrison Planetarium), he faced a conundrum. To solve the problem, he let the domes bulge out the top of the building. The additional three hills in the roofscape were added to mimic the hills surrounding Golden Gate Park, including Grand View Park, which served as an inspiration for Piano.
In addition, the 4.5-acre roof features a ring of solar panels (60,000 photovoltaic cells in all) along the perimeter. The "solar canopy" will generate 213,000 kWh of energy a year, fulfilling 5 percent of the academy’s energy needs and preventing the release of 405,000 pounds of greenhouse gas emissions annually.
The roof is composed of seven layers of material that work with the plants to create insulation (keeping the interior 10F cooler than a standard roof), reduce the urban heat island effect (by staying 40F cooler than a standard roof), lower noise (by 40 decibels), and collect rainwater. From top to bottom, the 2.6-million-pound living roof comprises:
(1) Coconut husk trays, filled with plants and 3" of soil
(2) Another 3" of soil
(3) An erosion-control blanket to retain soil and moisture
(4) A drainage layer to prevent plants from rotting
(5) An insulation layer
(6) A waterproofing layer
(7) A concrete slab
One of the first things in the blueprints of the new CAS was the 90’-diameter Morrison Planetarium, which dictated the design of the rolling living roof. In 1952, the academy was the first to open a planetarium with an operating star projector, designed and built by the CAS staff. The new planetarium takes the high seat as the largest all-digital planetarium in the world and with a 75’-diameter screen, it matched Los Angeles’ Griffith Observatory as the largest in North America.
Unlike most planetariums, the new Morrison Planetarium, which seats 290, is tilted at a 30-degree angel so visitors feel as though they’re sitting amidst the stars, not just looking up at them. The plaster and fiberglass panels that create the dome’s exterior are supported by a 100-percent-recycled steel frame and inside, the screen is constructed of aluminum panels speckled—unnoticeable to the eye—with tiny perforations that allow speakers and other equipment to be hidden out of sight.
For the first year, the new planetarium will show Fragile Planet, a 30-minute spectacular (narrated by Sigourney Weaver and produced with help from Industrial Light and Magic, Pixar, and Lucusfilm Animation) that takes visitors from the academy’s living roof and 60 million light years away to the Virgo Cluster.
The best seats in the house are the ones in the very center. And thanks to digital technology, you can actually sit in them, where as before, they used to be reserved for the star-projecting machine.
African Hall first opened in 1934 with 24 dioramas depicting the evolution of life—and quickly became a CAS favorite among visitors and San Francisco residents. It is recreated in the new building as one of only three exhibits transferred from the old academy to the new (the others are the pendulum and the alligator swamp).
Before the hall was demolished in 2004, the academy cast molds of the ceiling tiles and other architectural details to recreate the exhibit space as accurately as possible. The old ceiling couldn’t be used due to structural changes, including a ceiling height one foot lower in the new building than the old, but two exterior limestone walls were incorporated into the building (the only structural elements transferred from the old academy to the new).
The biggest challenge of recreating Africa Hall, CAS senior curator of invertebrate zoology Dr. Terry Gosliner said when he gave me a tour of the new space, was to take a classic hall and make it new. The solution: "Bring the dead to life," he said. To do this, CAS recreated 12 dioramas as exact replicas, added four new dioramas, and interspersed them with eight video stations, and five living exhibits, including a 25,000-gallon tank for the academy’s 20 African penguins (seven of which hatched at the aquarium over the past two years).
Rainforests of the World
After it was determined that the 90-foot-diamter Morrison Planetarium would command the east side of the new building, Piano, in a call for symmetry, decided to erect a second, 90-foot dome on the west side—thus becoming the first spherical living rainforest in the US and the largest living rainforest exhibit in the world.
The exhibit features a winding ramp to the top of the exhibit—passing through the recreated Bornero rainforest floor, Madagascar rainforest understory, and Costa Rica rainforest canopy—and a glass elevator that takes visitors down through the vertical zones and ends in the tunnel through the 100,000-gallon Amazonian flooded forest at the bottom of the dome. Constructing the dome and the curving walkway created a problem for the builders, because the radius of the dome changes from top to bottom. As a result, CAS hired a rollercoaster manufacturer to bend the steel—unfortunately a full-out rollercoaster was not in the contract and the flying will be left to the butterflies, who will cohabit the dome with 1,600 other animals.
Change and adaptation is a theme throughout CAS; written on the floor in the Islands of Evolution exhibit is a quote from Charles Darwin: "It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change." The trees in the living rainforest have grown one foot in the six months since they were planted in the dome and within five years they should shroud the light from the roof above by creating a canopy over the lower layers, said Dr. Chris Andrews, director of the Steinhart Aquarium and chief of public programs. Throughout the building, the floor creates 8-foot-grid with retractable floor-to-ceiling pillars hidden out of sight when not in use but able to hold banners or create a new exhibit space when required.
A couple weeks ago we gave you a sneak-peak of the Water Planet exhibit, which CAS calls the "heart of the Steinhart Aquarium," but the aquarium also includes an alligator swamp (with an albino alligator, one of the rarest creatures in the collection), the California Coast exhibit, and the Philippines Coral Reef.
The 38,000 animals in the aquarium represent 900 species and are displayed in over 500,000 gallons of water. The California Coast exhibit highlights regional aquatic life in a 100,000-gallon tank and the Coral Reef—the deepest largest living coral reef display in the world and the second largest—is a 212,00-gallon tank that features the "hotbed of diversity" found in the Philippines, senior aquatic biologist Charles Delbeek said. In an effort to retain realism, the five viewing windows of the Coral Reef represent five areas where CAS and collaborating researchers have studied the plants and animals in the Philippines reef.
Construction, by the numbers:
• 3, years of construction time from groundbreaking to opening
• 17, thickness in inches of the largest acrylic viewing panel (it weighs 40,000 pounds and separates the elevator shaft from the Amazonian flooded forest in the living rainforest dome)
• 18,000, weight in pounds of the heaviest steel beam used in the undulating roof (it stretches nearly 100 feet without the support of structural columns in order to curve across the top of the Morrison Planetarium)
• 500,000, gallons of water held in the six largest tanks in the Steinhart Aquarium
• 1.7 million, plants growing on the living roof
• 2.6 million, pounds of soil and plants that make up the living roof
• 11 million, pounds of recycled steel used in the building
• 137 million, pounds of locally sourced concrete used in the building
If you go:
The academy will open its doors to the public Sat., Sept. 27 at 9:30 am. The opening ceremony, which will feature live music, entertainment, and booths about sustainability, begins at 8:30 am. Admission is free on Sept. 27. Afterward, admission is $24.95 for adults, $19.95 for seniors ages 65 and over, $19.95 for youth ages 12-17, $14.95 for children ages 7-11, and free for children ages 6 and under. Don’t forget to show your bus transfer or MUNI pass if you travel by public transportation, you’ll get a $3 discount per person. Tickets can be purchased at the academy or on its website.
For more information about the academy and its grand opening, visit calacademy.com.
Images by Tim Griffith and courtesy the California Academy of Sciences.
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