Acting as a beacon for Shelby Farms Park in Memphis, Tenn., the First Tennessee Visitor Center grabbed the attention of the Design Award judges for its use of aluminum bar grate as the building envelope. One judge said he thought it was a pretty interesting architectural choice, and that it was a very impressive looking project. "There's something about it that's monumental for the program that it is trying to host," he said. "It feels like a brave project, using one element and repeating it everywhere as a cladding material."
Aluminum bar grate draws upon the past for new visitor center
One of the largest urban parks in the country, Shelby Farms recently implemented a master plan developed by James Corner Field Operations, New York City, to revitalize the 4,500-acre park into a nationally renowned landmark. As part of the master plan, the $50 million, 180-acre Heart of the Park was completed in 2016, and consists of an ensemble of buildings and structures located around the 80-acre Patriot Lake, which was recently renamed as Hyde Lake.
A Central Meeting Place
Centrally located, the Visitor Center creates a new icon for the reformed landscape and acts as the nerve center of the park while serving as a hub and point of arrival for visitors. Designed by Marlon Blackwell Architects, Fayetteville, Ark., the visitor center is an 8,000-square-foot building with a 7,560-square-foot covered porch. The porch, which is cooled by five, 14-foot high volume, low speed (HVLS) fans from MacroAir, San Bernadino, Calif., provides shade from the Memphis sun and functions as a central meeting ground for the community.
“The buildings were designed to engage the public and encourage the public to use the park and the various amenities that were designed around the park,” says William Burks, Assoc. AIA, project manager, Marlon Blackwell Architects. “The buildings itself support the public interaction with the park and the elements within the park itself, and are simultaneously civic buildings and park features, essentially.
The Visitor Center design draws upon the regional precedence found in dogtrot floor plans. Familiar to the south, the dogtrot floor plan creates public shade spaces and natural ventilation. Commonly designed as an outdoor covered connector between two interior spaces, Burks says basing the visitor’s center design off of this allowed them to separate the three distinct programs. “There’s the administrative side to the visitor’s center, the public interface and then there’s a restaurant,” he explains. “Those three programs needed to be simultaneously accessible in some instances, and discreet and separate, and the dogtrot allowed for that because the distinct pods that are created.”
Agricultural History
The Visitor Center’s role as a visual beacon for the park led to some of the material choices the architects made during the design phase. The designers drew upon Shelby Farms agricultural history as a penal farm for the city of Memphis. “We were simultaneously drawing on the history of Shelby Farms Park, and then bringing a lot of the built agricultural history of the place to create the civic building and its interface with the park,” Burks says.
“From the beginning, the building was always envisioned to be clad in some sort of perforated metal,” Burks explains. “The idea was to always provide shade, and have a kind of dappled light, where the sunlight can filter through a perforated surface.”
The designers explored different materials, including perforated metal and expanded metal, before settling on aluminum bar grating. Long used in agricultural construction, aluminum bar grating is a lightweight and durable product, and is self-supporting, which was important for the long spans that were required.
Reflective and Transparent
The cantilevered form glistens during the day from the reflected sunlight and glows at night when illuminated with site lighting. The designers wanted a reflective yet transparent material that would give the building the required visual impact. “The mill finish of the aluminum bar grate allows light to pass around during different times of the day,” Burks adds. “There’s lots of light play that goes on. So every time you come to the building, if you come at a different time of day or a different part of the year, you can get a different light play on the building, which is really neat to see.”
The project features approximately 16,151 square feet of aluminum bar grating with a 77 percent open area from P&R Metals Inc., Birmingham, Ala. It has 1/8-inch bearing bars locked to 1-inch cross bars every 4 inches by swaging. To attach the aluminum bar grate to the steel sub structure, the designers came up with a custom stainless steel J hook clip that would avoid a galvanic reaction, while preserving the long life of the mill finish aluminum. The custom clip also allows for directional adjustments, while keeping a tight alignment to preserve its taut appearance.
“The threaded J-bolt pulled the bar grate tight to the angled substructure, so the only direct contact between the steel substructure and through the aluminum was through the stainless J-bolt,” Burks says. “We used a rubber gasket that the fabricator used on-site to insulate the connection between the aluminum panel itself and the angled substructure. The J-hook allowed the fabricator to adjust the panels on-site to pick up any tolerances from the steel substructure during construction, and also prevented the metals from touching one another.”
According to Burks, the panels’ 77 percent transparency gives the building’s 30-foot cantilever a lighter presence over the porch it covers. The openness also allows air to move through the form, which provides a significant amount of cooling during the hot Memphis summers, along with the HVLS fans. “It’s a balance between trying to maintain a certain transparency and light play,” he says. “It was a delicate balance of treating our aesthetic needs and the cost constraints of the project as well.”
Additionally, the aluminum bar grating helps mitigate the solar exposure for the buildings. “If we hadn’t used the
[aluminum bar grate], exactly like this, we would have had to construct different wall assemblies or passes just to deal with solar exposure, and it would have affected the design of the building overall,” Burks explains. “So, not only did we get the material we wanted, but we also got the aesthetic that we wanted.”
First Tennessee Visitor Center at Shelby Farms Park, Memphis, Tenn.
Completed: September 2016
Total square footage: 8,000-square-foot conditioned space with 7,560-square-foot covered porch
Owner: Shelby Farms Park Conservancy
Master planner/landscape: James Corner Filed Operations, New York City, www.fieldoperations.net
Architect: Marlon Blackwell Architects, Fayetteville, Ark., www.marlonblackwell.com
General contractor: Montgomery Martin Contractors, Memphis, www.montgomerymartin.com
Metal fabricator/installer: Tri-State Ironworks Inc., Memphis, www.tristateironworks.com
Aluminum grating: P&R Metals Inc., Birmingham, Ala., www.prmetals.com
HVLS fans: MacroAir, San Bernadino, Calif., macroairfans.com
Storefront system: Tubelite Inc., Walker, Mich., www.tubeliteinc.com
Photos: Tim Hursley