Rejuvenation of a Historic Power House
Owner: Port of San Francisco
General Contractor: Orton Development Inc.
Lead Design Firm/Architect: Marcy Wong Donn Logan Architects
Structural Engineer: Nabih Youssef Associates
Landscape Architect: GLS Landscape Architecture
Subcontractors: Allied Heating & Air Conditioning Co.; Architecture & Light; Helix Electric; Preservation Architecture
Constructed in 1912, the building originally housed compressed air and hydraulic power-generation equipment and served as an electrical substation that transformed and distributed electrical power for a 69-acre shipyard along San Francisco’s waterfront. A stylistically formal yet eclectic exterior that mixes Beaux Arts details with a mission tile roof belies the building’s original technical function. The interior features hardwood, marble and brass finishes.
In restoring the structure for adaptive reuse as a technology company office, the project team had to create sufficient usable space to justify the capital expense of the renovation while preserving the building’s historic character. To make the large lower level usable, three of the four original massive concrete foundations that once supported main-level compressors were demolished.
The remaining foundation was left in place to support a compressor retained as a historic artifact. Because of limited interior access, demolition work was accomplished largely using small-scale equipment. The resulting floor openings were infilled with a distinctive contrasting surface material that celebrates the original layout.
Taking full advantage of the main level’s 38-ft-high vertical clearance, the project team added a partial mezzanine constructed of black-painted engineered wood beams with tongue-and-groove wood decking that was stained to match the building’s original exposed wood roof deck above. The height of the mezzanine was set to conceal the new floor behind the existing window mullion so that the views from outside into the building would remain unchanged.
The original building’s 10-ft grade change between the main-level entry and the lower level allowed the project team to integrate a 2,600-sq-ft addition capped by a roof deck aligned with the main level.
Work was carefully coordinated to preserve the historic district’s main underground electrical feed, located beneath the addition. A new deck-access stair wraps around an existing maintenance hole to provide service access as needed.