Incorporating the existing bank with the new building involved removing two facades and lowering the first floor to better match the street and new building. Highlights of our structural design for the existing building include the following:
Removing the existing, deteriorated cinder concrete floor slabs at the second and third floors, while retaining the steel framing
Replacing the second and third floor slabs with new concrete slabs to support higher live loads, allowing for more flexibility in using the space
Removing and replacing the existing first floor framing
Removing three columns in the first level to provide an open layout and resupporting the second floor framing with a system of transfer girders
Repairing corroded beams and columns
Evaluating the existing mat foundation for the new loading and advising the architect on ways to avoid overloading the mat and subgrade
SGH designed the new building structure, comprising composite steel framing with a combination of moment and braced frames to resist lateral loads and a mat foundation to accommodate poor soil conditions. Our design included strategically placing framing and selecting the size and thickness of structural components to maximize usable space in the tight site.
We also consulted on the building enclosure, including below-grade waterproofing, limestone cladding, and cornices.
SGH provided construction phase services, including observing ongoing work and helping address unforeseen conditions, particularly below grade. We also helped monitor adjacent buildings to track movements during construction.