After nearly 10 years of planning and fundraising efforts, the
Smithsonian Institution broke ground on Feb. 22, 2012 for the National Museum
of African American History and Culture. When the building opens to the public,
it will become the only museum dedicated
to documenting the history, life and culture of African Americans.
Located on a 5-acre site on the National Mall between the National
Museum of American History and the Washington Monument, the museum encompasses
322,600 square feet with five levels above grade and four below grade.
Appropriately, the museum’s design is distinctive among other structures
on the National Mall. Its façade consists of 3,600 customized, cast-aluminum
panels known as the Corona. These bronze-colored panels call to mind the
craftsmanship of enslaved workers in the pre-Civil War cities of Charleston and
New Orleans and create a distinctive impression for the museum representing
traditional African architecture.
Just as the museum’s architecture makes a unique design
statement, its landscape design also distinguishes it among nearby museums and
monuments. Incorporating the museum into the larger configuration of the
National Mall, the landscape design integrates the site within the museum’s
larger story. According to the landscape architecture firm, “The site is
designed to encourage visitors to extend the museum experience outside and to
linger and reflect on the important narratives being told within.”
Granite played an integral role in meeting design
goals, as approximately 37,000 square feet of Mesabi Black® in various finishes were used for numerous hardscape
elements such as paving, wall facing, wall coping, steps, curbs, benches, and
bollards. A majority of the stones for the project were modeled in 3D software,
which allowed the fabricator to coordinate with the landscape architect and
ensure the designs met expectations. Due to the project’s complex nature, an
extensive amount of coordination between the fabricator’s drafting team and the
architect ensured the 3D models were accurate prior to fabrication. Once the
design team approved the fabricator’s drawings and models, the fabricator
converted the models into a file for use on a 5-axis CNC machine.
CNC technology was critical for creating the
intricately crafted cubic wall of black granite encompassing the site’s
perimeter. Most of the walls feature a highly polished finish. However, a
combination of polish coping and Diamond®
8 facing was selected for the museum’s north wall, which
serves as the museum’s main entrance. The north wall spans approximately 340
feet across the front of the museum, running parallel to Constitution Avenue.
The less reflective, Diamond 8 finish was selected due to concerns over too
much reflection off the wall at the highly traveled entrance.
Fabrication of the granite pieces for the north wall
proved particularly challenging because of the wall’s slight radius and
continuous bullnose. The fabricator had to produce each of these stones at
precisely the same thickness to ensure an exact alignment at installation.
Most of the wall’s cap pieces were milled by the
fabricator’s 5-axis CNC machine and then finished by hand to create the
bullnose. With multiple workers applying a bullnose to hundreds of pieces,
accomplishing the precision required for alignment requires an exceptional
level of coordination and craftsmanship.
In addition to the Diamond 8 and polish finishes used
for the site’s walls, various finishes were used for additional granite
elements at the site. Bench seats feature a polish finish, and the curbing
features Diamond 8. The paving – encompassing 25,000 square feet of granite --
and stair treads feature Diamond 10, which is an ideal slip-resistant finish.
The museum is designed for LEED Gold certification and
is scheduled to be opened by President Barack Obama in September 2016.
2016 Pinnacle Award Winner: Commercial Exterior
Photo credit: DC Real Estate Photo