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Courthouse Takes Form of Contemporary Cube
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Exterior rendering of the new federal courthouse in Salt Lake City is sheathed in a variegated system of anodized aluminum sunscreens punctuated by metal extrusions
The new federal courthouse in Salt Lake City is sheathed in a variegated system of anodized aluminum sunscreens punctuated by metal extrusions. Courtesy of Reaveley Engineers + Associates

Sunscreens help a federal courthouse in Salt Lake City control daylight, while a compact design helps meet security needs.

May 27, 2014—“This is one of those projects that I was quite sure would not be finished by the time I ended my career,” says Mark Harris, S.E., LEED-AP, a senior principal of Salt Lake City-based Reaveley Engineers. He’s referring to the new, as yet unnamed, federal courthouse in Salt Lake City, a building that has been planned since 1996 but just opened in April.

The project was initially planned as an annex to the existing neoclassical Frank E. Moss United States Courthouse; bankruptcy courts would move to the new building while district and magistrate courts would remain in the old. “At some point they determined that they’d prefer to move the district courts out of the old building and into the new building,” says Stephen Dayton, a project architect with New York-based Thomas Phifer and Partners and the lead architect for the new courthouse.

Dayton explains the change: “The primary reason for that was the district courts had some fairly specific security arrangements with regard to judges and prisoners and how they move around in the building.”

Additionally, the safety of buildings themselves has been a major concern for the General Services Administration, which owns and operates such federal buildings, since the Oklahoma City bombing in 1995—a concern that’s only intensified since the attacks of September 11, 2001. The agency now requires its buildings to have a 50 ft defensive setback from the street.

“The old courthouse really wasn’t set up to handle these situations—since we were designing this building from scratch, we could plan all of that into new design,” says Dayton. “The requirements for prisoner handling were not quite as stringent in bankruptcy court, so they could remain behind, in the old courthouse.”

Once a new structure was agreed upon, the project went through several rounds of design. Following an initial design phase, a nearby meeting hall that dates back to the late 19th century had to be cut loose from its foundation and relocated across the street. A second design phase ended when the government determined that an existing building on the site was too close and posed a security risk. The GSA purchased and demolished it. From there, architects finally had a clear site on which to imagine a stand-alone courthouse for district courtrooms. 

Rendering of a three-story circular staircase in the building's atrium

A three-story circular staircase in the building’s atrium leads
visitors up to a ceremonial courtroom. Courtesy of Reaveley
Engineers + Associates

Federal courthouses have specific requirements with regard to courtroom dimensions and separate circulation corridors for prisoners, judges, and the public. The GSA required Phifer to develop several proposals, which were then vetted by the GSA, the courts, and other stakeholders in Salt Lake City, along with the architects themselves. One proposal called for a tower with two courtrooms per floor, but that was ruled out as inefficient. Another spread the program across a lower building that covered the entire site—but that didn’t leave enough space for the 50 ft security perimeter, or for a planned future expansion. That left the design that was chosen, a 10-story glass-and-steel cube with four courtrooms per floor. The design proved the simplest and most efficient, allowing courtrooms on each floor to share critical back-of-house functions.

“It seemed like it was going to allow us to spend a little bit more money on finishes and details,” says Dayton.

The design was completed around 2009, but mounting costs and then the recession waylaid the project until January 2011, when construction finally began. The 370,000 sq ft courthouse will contain 10 courtrooms (with room for 18), along with judges’ chambers, a U.S. attorney suite, and probation and pretrial offices. A ceremonial courtroom is on the third floor, used to swear in new citizens or as a courtroom for high-profile trials. Two restricted parking levels sit below grade.

Daylight was a key theme of Phifer’s design. “We wanted to bring natural daylight into the courtrooms, and that was an intention from the very start,” Dayton says. Courtrooms were positioned at the corners of the building, so each one has an entire wall of translucent and clear glass. “You don’t see that in a lot of courthouses.”

The architects wanted to bring daylight to the office spaces as well so that people inside could enjoy the spectacular views of the Wasatch and Oquirrh mountains that surround the city. Additionally, they wanted the building to feel transparent without being porous.

But, Dayton notes, “When you make a glass building, you can’t just make a glass building. You have to deal with the sunlight and heat gain and glare. Once we made that decision, we had to circle back and think about how we would control the sun around the building.”  

The solution was a system of anodized aluminum sunscreens that shade roughly 40 percent of the building and, along with ceramic frits on the glass, help control solar gain. The screens vary across each side, fine-tuned to the orientation of the sun, and the panels are broken up by metal extrusions that were milled to create as much transparency as possible without compromising their shading. “We didn’t want to make people feel like they were too contained,” says Dayton.

The louvers are less dense in areas in which people are working (to open up the views) and denser in circulation spaces, which are used less frequently (and where the narrower corridors are more sensitive to heat gain). The circulation spaces for the judges have the densest louvers of all.

The architects didn’t want to see columns from the exterior of the building—if they were located behind glass, they would show up as a dark spot in the building when the courthouse was lit up at night. So engineers for Reaveley moved the structural columns 6 ft away from the windows and cantilevered the edges of the floors out 6 ft from all sides. To accommodate the judges who occupy corner officers on the top two floors of the building, the engineers removed the corner columns to create more space. The columns are not entirely uniform in their spacing; they are shifted several inches here and there to accommodate the building’s various interior programs.

The spiral staircase is suspended from the fourth floor by 12 steel tension rods; the rods are attached to the ground floor via springs

The spiral staircase is suspended from the fourth floor by 12 steel
tension rods; the rods are attached to the ground floor via springs.
Courtesy of Reaveley Engineers + Associates

The building features a 10-story atrium that brings light in through a skylight above the elevator core. The center of the building features a 10-story work of art by artists James Carpenter, which includes reflectors at the top of the atrium that channel daylight down to the ground floor.

One of the highlights of the atrium is a three-story spiraling staircase. Harris says, only half-jokingly, “We might have as much engineering in that stair as we have in the rest of the building.”

The circular stair connects to the first three levels. But the building is a moment frame, which means that with no bracing or concrete shear walls, all its lateral stability comes from the connection between the beams and the frames. It’s a system prone to significant lateral movement under a major event like an earthquake. The interstory drifts could be as much as 3 to 4 in. per floor. “To design the connections with the floors, when the floors have the potential to shift at every floor, was a real challenge,” Harris says.

The stairs are suspended from 12 steel rods that are attached to the underside of the fourth floor. Vertical wood slats, connected via rings to the rods, circle the staircase. The rods go all the way down to first floor. “In order to keep that scrim of wood lattice stable, those rods have to connect to the floor,” Harris says. Otherwise, the wood elements would rattle around. On the other hand, connecting the wood to the floor, via the rods, means that during an earthquake, the uppers floors could displace side to side enough to stretch the rods to the breaking point—taking the whole staircase down with them.

“Under day-to-day operations you want [the] rods tight and connected to keep [the] lattice tight, [but] under an earthquake you need more flexibility,” he continues.

The solution was to build steel pockets underneath the first floor. Inside the pockets the rods connect to springs. The springs keep the rods in tension under ordinary use, but in the event of an earthquake, there’s enough play in the spring to absorb the deformation of the floors above.

The soil on the site was poor, with low bearing capacity, so the engineers turned to a more forgiving full-raft mat foundation. Because the building’s southwest corner rises about a dozen feet above street level, they had to build up the grade for the plaza area around the building. But using soil could have created a drag force that could possibly sink the whole building.

Instead, the engineers used blocks of geofoam, which is significantly lighter than soil (2 lb per cubic foot versus 125-130 lb). Sections of foam were cut 4 ft deep to make room for tree plantings.

The west side of the building, where the public entrance is located, features three rows of trees leading to a wide set of steps going up along the entire width of the building, as well as a reflecting pool. The landscape architecture, designed by E.A. Lyman Landscape Architects, of Sandy, Utah, also features simple grasses and two rows of trees lining the other three sides of the building.

Still, while the architects in Salt Lake City appear to appreciate the sophisticated design, residents of the city are not entirely sold. The facade and landscape design of the building have been criticized, as has its overall look and shape. A Salt Lake City Tribune article likened it to the Borg cube ships from Star Trek. “It’s not a great feeling, I’ll be quite honest,” says Dayton about the criticism, “but I do think we have an approach that is not about bringing a style to the table. Our approach is more about trying to understand all of the challenges of a project and coming up with solutions in a unified and holistic way to answer those challenges. So the design comes out of a process.”

He notes that it was a process with significant stakeholder input, but he knows that forward-looking architecture doesn’t always connect with a community right away. “It’s not unusual that it takes time for people to warm up to it. In this case our hope is [that] as those people experience the building and maybe go inside and look around and see that the inside has its own character, that they’ll start to appreciate it more.” The building, he adds, will also change once the landscape starts to take hold.

Still, he says the firm is not taking anyone’s view as a blanket condemnation. “We’ve received quite a lot of positive feedback, too, and are hopeful the building will grow on people. We think it’s going to be a good building for the city.”


 

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