With an expansive glazed facade and warm wood ceilings that subtly reflect light, the Los Gatos Public Library emits a soft glow at all waking hours, but the best time to see it is at dusk. That's when the lighting program switches on and slowly sends a wash of amber (or blue or purple) across a band of frosted-glass panels tucked at the base of the second-floor windows. The color change, which spreads from the center of the facade outward, takes about 40 minutes to complete and happens almost imperceptibly. It's the kind of touch that helps the already lamplike library advertise itself as a beacon for this small, mountain-edged city south of San Francisco Bay. The stretch of glass that houses RGB color-changing LEDs was originally meant to be empty, a leftover space from the raised-floor ventilation and electrical system. “We were just going to put a blank thing there,” recalls Chris Noll, principal of the Berkeley, California'based firm Noll & Tam Architects. “And I went, 'Oh, I want to do something with that. Why don't we have some fun?' ”
Working with Illuminosa lighting consultants, the architects chose the concept of a lantern in the woods for the usual associations between knowledge and light, but also to help the public see the building on a site with a large setback and ample tree cover. They designed the steel-frame building as a long, transparent rectangle and oriented the facade to capture northern light. At two stories and 30,250 square feet, the LEED Gold'certified library triples the size of its old quarters inside the neighboring civic center. The new building, which opened in February 2012, includes stacks and storage for the library's 120,000-item collection, a children's library, a reading room, a computer lab, and a community meeting room, as well as a teen center and a local-history section that pop out from the north and south facades, respectively, in a matched pair of cantilevered bay windows.