Program: A 12-story, 332,000-square-foot speculative office building set into San Bruno Mountain alongside the highway. The project includes a performing arts center and space for a health club and retail on the ground floor, a childcare center and outdoor play area on the second level, and a 1,000-car garage. The structure was designed as part of a pair; the second tower has been delayed due to market conditions.
Design concept and solution: Conceiving Centennial Tower as a sculptural object set into the base of the mountain, the architects wanted the building to both play off the topography and contribute to its rehabilitation. They aimed to make the structure a beacon for travelers heading into south San Francisco while also keeping its bulk in check. The project takes up only 8 of 20 acres on the site, which was damaged during construction of the highway; the remainder is set aside for a conservation plan, which includes a replanting program to restore the mountain's edge. The architects designed a steel tower with a rounded, veil-like curtain wall whose curves echo the shape of the terrain and the arcs of the highway's ramps. (The garage is embedded in the valley behind the tower to help conceal some of the project's mass.) For motorists passing by, the building's shape shifts and its color changes. Differences in light affect the colors of the facade, which vary from silvers to blues to warm hues depending on the time of day. The architects used the largest amount of clear glass on the east side of the building, gradually replacing it with spandrels toward the southern facade. Inside, they used finishes inspired by the tower's surroundings, from limestone walls and floors in the lobby to dark walnut in the elevator lobbies and cabs.