Project Profile: 7 East Redwood Street
Scope of work:
Removal, replacement of terra cotta cornice and other masonry repairs
BC&E Member companies involved:
Structural Preservation Systems
By the time Structural Preservation Systems was called in to assess a project at 7 East Redwood Street, the building’s condition was already creating a life safety hazard. The historic, terra cotta cornice on the 19th story had decayed to the point that pieces had fallen to the sidewalk below and the owner had erected overhead protection to safeguard pedestrians.
Structural’s assessment confirmed that the 100-year-old terra cotta along the Redwood and Light Street sides of the building was “in extremely bad condition,” said Vincent Armeni, Senior Superintendent. “When terra cotta isn’t maintained, you get water infiltration that reaches the supporting steel. Corrosion and expansion of the steel starts and that’s what blows the stone apart.”
Structural erected netting around the cornice and removed all of the stone which ranged from 50 to 300 pounds apiece, and all of the steel after concluding that both were too damaged to repair.
Rather than install new terra cotta on the top of the building, Structural replicated the intricate cornice in CastCotta, a cementitious product. To accurately recreate the dental elements, floral details and cornice capstone, craftsmen from CastCotta completed a long process of measuring the building, verifying dimensions of the cornice and drawing each stone independently, Armeni said.
Working on mast climbers outfitted with lifting tables, the Structural crew then began installing more than 430 pieces that would comprise the new cornice.
“We learned a lot of lessons as we worked on the Redwood Street side of the building,” said John Lunn, Construction Manager.
Crew members honed processes to efficiently and expertly complete installations. By the time they started work on the Light Street cornice, the crew was ready to embrace a new, more complex but faster work sequence. They would complete all work in one zone of the building before moving on rather than completing one task across the entire façade before starting the next task. The result, Lunn said, was the crew finished the Light Street work 30 percent faster.
In addition to the creation of a beautiful cornice, “I’m really pleased with the training aspect of this project,” Armeni said. The project’s superintendent significantly increased his stonework skills and has since been assigned to other, demanding jobs. Other Structural team members learned how to fabricate cementitious pieces to replace damaged window heads on the Mercer Ally side of the building.
Those skills will likely be needed on future jobs, Armeni said. “There are a lot of buildings in Baltimore City that were built around the same time and they are experiencing the same level of deterioration,” he said.