By Marcy Marro, Editor
In my interview with Hal Davis, FAIA, senior vice president at
SmithGroupJJR, Washington, D.C., one of the
four architecture firms involved in the Smithsonian's
National Museum of African American History and Culture
(NMAAHC), featured in this month's Building
Profile, he shared so much more information than I could fit
into my article. So, I went back over some of the points he
mentioned, and thought I'd share some additional insights into the
19th museum on the National Mall.
On the south side of the museum from Madison Drive is an entry
porch that is a defining element of the design, and oneDavis says
is clearly derived from African American homes. "The porch was the
welcoming area to homes and the place where families gathered," he
said. "The porch at the museum is a representative gesture of that
The porch is supported by two columns at each end of a 200-foot
span and cantilevers out over the water feature below. The water
feature itself is evocative of African Americans crossing the water
to arrive in America, Davis adds.
Lenses and Views
Throughout the corona, Davis says there are certain openings or
lenses that allow visitors to view various points of significance
on the Mall and to provide moments of context. "Lenses on the north
face the Ellipse and the White House," Davis said. "On the east,
the lens views are to the Capitol and the National Archives. On the
south, they are to the Jefferson Memorial and Tidal Basin."
"On the west," Davis continued, "there are two major openings,
one slightly angled vertical opening focused on the Washington
Monument. This particular lens you can walk out into as it
cantilevers into the west atrium inside the museum and brings the
visitor very close to the exterior glass. The other west-facing
opening is the long horizontal window at the top that allows the
visitor a wide expansive view of the Washington Monument grounds
down to the Lincoln Memorial."
The museum features a variety of galleries for visitors to
explore. The History Gallery is part of the 65 percent of the
museum that resides below grade. It is a three-level space to which
visitors arrive by a large elevator. "This space moves the visitor
from fairly tight and confined entry spaces to an expansive
65-foot-high exhibit hall, which I believe symbolizes the
incredibly confining space on slave ships to the hoped for freedom
to come," Davis explained. "Each level in this portion of the
History Gallery rises above and is accessed by a series of ramps
that exits into the north atrium."
As you exit from the History Gallery, on the right is the
contemplative court, which allows visitors a moment of reflection
and decompression. The upper galleries are the celebration
galleries expressing the many accomplishment, talents and
contributions made by African Americans to this county and the
world, said Davis.
The Museum Roof
When designing the museum's roof, Davis said the roof had to be
designed to eliminate any visible equipment or other materials that
might provide the appearance of a typical building rooftop. This is
because the building rooftop is uniquely visible from the top of
theWashington Monument, making it the "fifth façade."
As with all projects, there are always challenges to be figured
out. For the NMAAHC, the challenges came as early as during
excavation, since as Davis explained, much of D.C., and this area
in particular, was once part of Tiber Creek. The site is comprised
of deep earthen fill and a high water table that is within 10 to 12
feet of the surface.
"The original design was based upon constructing a support of
excavation wall (SOE) around the full perimeter of the site, 6 to 8
feet outside the actual foundation walls of the building," he
explained. "It was to extend down to disintegrated rock and provide
a cut-off of the surrounding groundwater. The area below the
building would then have a network of drain tile to capture
whatever water seepage came into the site and convey that to sump
pumps. That removed the issue of the water table surrounding the
foundation walls and bottom slab from creating hydrostatic pressure
on the building below grade. However as the SOE was being
installed, large boulders and other deleterious materials
interrupted the integrity of the SOE, creating breaches in the SOE
and allowing water to flow at a high rate into the site excavation.
That required the entire foundation system to be redesigned to add
more piles to hold down the slab and the change to a complete
waterproofing of the foundation and walls."
To read more about the Smithsonian's National Museum of African
American History, click here.