California leading

California has a new hit: the state's new Academy of Sciences building in San Francisco has been drawing increasing plaudits from both professionals and the public alike. With the strictest of environmental demands, architect Renzo Piano has created a building " that is visually and functionally linked to its natural surroundings, metaphorically lifting up a piece of the park and putting a building underneath, " he says. The new building houses the Academy's original array of 12 buildings, which were built over eight decades, in a single landmark building that places a visual and intellectual emphasis on the natural world. Topped with a hectare-sized living roof, the new California Academy of Sciences involves a wide range of energy-saving materials and technologies. Piano wanted the living roof to comprise species native to northern California and worked with Academy botanist, Frank Almeda, and a team of living roof specialists to develop his plans. The mounds on the roof were designed not just for visual distinctiveness but also for energy conservation. These mounds, which incorporate slopes of more than 60 degrees, draw cool air into the centre of the building, naturally ventilating the surrounding exhibit spaces. These comprise a planetarium, several tracts of rainforest, a colony of seabirds, reptiles, bats, a coral reef and many others. While several of these features were found in the old buildings, the new building has allowed expansion and development. The living coral reef is now housed in an aquarium more than six times larger than previously, and natural lighting through panels in the green roof has been maximised to reduce the need for artificial lighting sources. " You can say that the building is made of shadows, " says Piano. " Being inside is like being under a tree in summer. The green roof with its bubbles is like foliage wrapping itself over branches. And Pacific breezes make sure you don't feel trapped inside some heavy institutional building. " And the roof does more than attract wildlife: it helps keep the building's interior 6ºC cooler than a conventional material would, while dampening noise in the galleries. The new environment-friendly building for the California Academy of Sciences in San Francisco is proving a huge success with staff and public alike. Nigel Williams reports. Green lines: Architect Renzo Piano has pushed the boundaries for the environmental credentials of the new California Academy of Sciences building in San Francisco.