Energy: Open Windows

San Francisco boasts a lot of awesome architecture: the towering headquarters of Transamerica Corp., which looks like an elongated pyramid; the severe, deep-carnelian granite Bank of America building; the hollowed-out Embarcadero Hyatt Regency, its interior a modern evocation of a Babylonian hanging garden. Bay City boosters will soon have another unusual building to talk about. Construction has just begun on the 19-story Northern California headquarters of Pacific Mutual Life Insurance Co., which Architect William Pereira reckons is the first high-rise office structure with openable windows to be built in the U.S. since World War II.

Pereira, who designed such pioneering structures as C.B.S. Television City in Los Angeles and the library at the University of California at San Diego, got the idea from a 24-story building owned by the Crocker National Bank in San Francisco. Although it was built in the 1920s, says Pereira, “it is always 100% occupied, and one of the principal reasons is that it has openable windows.” He designed the Pacific Mutual building not only as a fond bow to the city’s tradition, but also to cut energy use by 15% to 20%. And he estimates that the new building will cost no more, and offer tenants greater variety, than conventional offices. Besides sliding French windows, there will be balconies that provide shade, individually controlled lighting known in trade parlance as “task lighting,” and heat pumps that transfer hot air to chilly spots and vice versa. Tenants who prefer air-conditioning in hermetically sealed offices can create that environment by using the heat pumps.

Pereira figures that similar buildings would be practical almost anywhere in the U.S., except in very humid regions. In fact, he often opens the windows in the five-story Los Angeles building where he works. Says Pereira: “I’m a fresh-air fiend.”