Constructed in 1912 and now owned by the Port of San Francisco, this historic building’s original purpose had been to generate compressed air and hydraulic power and serve as an electrical substation that transformed and distributed electrical power for a 69-acre shipyard along San Francisco’s waterfront. Designed by Ecole des Beaux Arts educated American architect, Charles Peter Weeks, the Powerhouse’s stylistically formal yet eclectic expression (including Beaux Arts details and mission tile roof) belies its original, purely technical function which crammed the interior with electrical equipment serving a maritime industrial complex founded in the 19th-century. The Port selected our team of developer, architect and engineers to restore for adaptive reuse this structure which is located in the “Historic Core” of Pier 70. The project along with seven other historic buildings is listed on the National Register of Historic Places.
The Powerhouse’s industrial infrastructure (massive compressors, 5-ton gantry cranes) and genteel early 20th C elements (original factory lighting fixtures alongside hardwoods, marble, brass, and mosaic tile) are cherished by the current generation of young San Franciscans. To make possible this re-use of the old building as modern offices for a tech company, the developer needed to clear out the interior of all but one salvaged and refurbished historic compressor (one of original four compressors). This historic compressor – now a sculptural historic element, along with cranes and the building shell itself, are high-lighted with LEDs. Once the space was cleared of compressors, electrical switchgear and other equipment, the Powerhouse’s 48’ height at its main level ridge was further accentuated by 18' tall windows.
A new mezzanine level is constructed along the south and the west sides of the structure, providing an overview of the main level. The mezzanine structure and the stairs leading to it are the most significant architectural interventions within the old building. The heavy-timber construction of the new mezzanine and new stair treads is detailed to complement the exposed historic wood roof structure above, while the new steel balustrades at mezzanine guard rails and stair recall the historic exposed steel roof trusses. The mezzanine also serves an architectural purpose of defining the entry / reception area at the building’s “front door”. Facing the entrance door and below the twelve-foot ceiling resulting from the new Mezzanine above, the custom concrete reception desk and freestanding hardwood entry wall have dual functions. These elements separate the main level’s open work space from the distraction of entrances and exits.
In adapting the Powerhouse for office use, the architect’s and developer’s design objectives include arranging spaces to maximize the inherent attributes of the building such as vistas of a park in one direction. The building’s main level, mezzanine, and lower level addition are blessed with abundant daylight and views. Thus, nearly all work areas are located on these levels, as well as some meeting rooms.
In addition to the main existing level and a new mezzanine, the building has a lower level, which has low ceilings and is below grade along one side. For this reason, the areas without much natural light at the lower level accommodate bathrooms, conference rooms with video projection, bathrooms, and kitchen. A new 2,600 sq. ft. addition to the lower level provides daylit open work area while the roof of the addition provides a deck accessible from the building's main floor level; both deck and main level overlook a Port of San Francisco park and a bridge beyond.
Throughout the building, the architectural lighting design with new lighting fixtures and other interventions are instrumental in transforming the interior from an electrical powerhouse to a humane and uplifting environment for the technology workers. These elements do not imitate the Powerhouse’s historic architectural features, but rather endeavor to enhance by contrast with the original Powerhouse. The lower level, which does not have the benefits of the main level’s lofty height and daylight, is where the importance of architectural lighting is especially significant. Thus the team endeavored to transform the windowless, low ceilinged spaces with architectural light, such as the hallway which is enlivened by sculptural pendant light fixtures that make the circulation a diverting experience.
Donn Logan and Marcy Wong formed their Berkeley, California firm in 1999. Over more than a decade, the partnership has developed a portfolio of work that expresses their goals of outstanding and environmentally sound design. The firm’s interests span issues of the built environment ranging from architectural expression to technological innovation, to cultural manifestation, adaptive reuse, urbanism and planning. Marcy Wong Donn Logan Architects is devoted to producing architecture that is rooted in its time as well as its place, taking advantage of contemporary advances in materials and techniques to execute buildings that are forward‐thinking while remaining sensitive to their context. The firm’s principals have developed a design approach that treats each context – physical as well as cultural—as the seed for a unique solution in architecture.