San Francisco, CA
530 Bush Street
Located in the city’s financial district, 530 Bush Street was originally a power plant. The owner planned to convert the eighty-year-old building to office space and wanted to address cracks and spalling in the terra-cotta cornice that created a life safety problem, severe corrosion of structural steel components, water intrusion at walls and parapets, rooftop planter leaks contributing to material failure, and lead-based paint on concrete walls above cornice. SGH conducted a condition assessment of the five-story facade and developed a rehabilitation program.
SGH assessed the condition of the steel-framed building with masonry infill and a terra-cotta-clad cornice with roof planter above. SGH developed a repair program that included the following:
- Removal and restoration of severely cracked cornice pieces reinstalled with new supports
- Removal and patching of spalled terra-cotta and concrete columns above the cornice
- Cleaning of corroded steel and treatment with a corrosion inhibitor
- Replacement of the cornice roof and roof above the top-story windows and development of a waterproofing design for new roof garden
- Consultation for lead paint abatement
We also implemented cathodic protection for the structural steel supports in the cornice which made this project the first known application of cathodic protection on a steel-framed, masonry building facade in the United States. The cathodic protection system utilized twenty-three titanium anodes and low voltage direct current to control corrosion of the steel components.