The new seven-story Nathan Deal Judicial Center in Atlanta, Ga., was designed to reflect its status as a state government building and to complement the classical architecture of the nearby Capitol Hill district.
Early design ideas included cladding the building in marble to match other state government buildings in the district, or using limestone cladding to correspond with the Georgia State Capitol. However, the design team ultimately chose to use precast concrete because it could deliver the desired stone look in a durable, cost effective, and energy-efficient package. Additionally, a precast concrete structure would also be faster and easier than the alternatives to erect on the tight jobsite.
Sizing Panels for Long-Span Placement
Early design-assist workshops helped the design team fast-track project coordination; fine-tune the precast concrete wall panel sizes for efficient shipping, crane lift, and installation; and control the location of panel joints to support the overall facade’s design.
The combination of spray foam insulation on the back of the precast concrete panels and traditional stud wall framing with batt insulation at the building perimeter provided excellent R values (R-30) for wall assembly, significantly exceeding code minimums. Working in tandem with high-performance glazing, the exterior envelope contributes to lower energy costs and greater occupant comfort, while eliminating road noises from adjacent highways.
To mimic the limestone on the adjacent Capitol Building, the precast concrete producer developed a perfect color match using a blend of local materials combined with a quality cement and dye combination. The faces of the panels are acid etched to look like Indiana limestone, which is normally cut from large blocks.
During construction, the siting of the building and adjacent interstate retaining walls restricted crane access; therefore, all panels had to be sized below crane capacity to achieve an extended reach. The panel sizes were coordinated with the panel articulation desired by the design team and are indiscernible.
Because the entryway panels are granite clad, they had to be broken up several times to stay under crane load capacity. At the colonnade, the column surrounds had to be installed first, and then the spandrels were installed at the back side. The erector shimmed these spandrels off the column surrounds to keep the tube beams from rotating; after this was done, workers were able to install the front spandrel panels to be balanced.
The result is a stunning companion building to the State Capitol, reinforcing this new building’s status as a central home for state government.