The Mercedes-Benz Stadium in Atlanta features a kinetic roof that opens
and closes like a camera aperture.
TFhrormothue bgeghinnintgh, tehe dResiognoinftent of the Mercedes-Benz Stadium was to
snaked through the installed façade steel
from the ground to their ﬁnal position.
Anderson says several steps
were taken to ensure a safe, quality
create a unique, standout structure that would not only be bright, but one that
would create a fan experience. The HOK architectural team was able to accom-
plish that with a number of unique features--including one impressive roof.
Architects created a kinetic roof structure that opens and closes like a cam-
era aperture. According to architects, the semi-transparent roof was inspired by
the Roman Pantheon. It consists of eight triangular ethylene tetraﬂuoroethylene
(ETFE) panels that move in unison along 16 tracks. More than 143,500 square
feet of ETFE “pillows” are used in the petals alone. In the closed position, the
petals lock together to form a watertight seal.
“Safety life lines had to be installed
on the curtainwall support steel as
tie-off for the anchor crew; the an-
chor crew worked off the support steel
beams to anchor the curtainwall back
to the structure,” he says.“A lot of time
and care went into positioning the 75-
ton crane so that units could be pulled
off the ground and snaked through the
façade steel without damaging the unit
or other trades work.”
Advances in parametric modeling
and software, Drosos adds, will con-
tinue to create opportunities for more
complex structures in the future.
“We wanted to challenge the utilitarian nature of existing retractable roofs,”
says HOK’s Bill Johnson, senior vice president and design principal for Sports +
Recreation + Entertainment. “Conventional kinetic roofs feature sliding panels
that don’t contribute to the aesthetic of the venue. Our vision in Atlanta was to
create a roof that would change the conversation about kinetic architecture and
contribute to the game-day experience. It is beautiful and sculptural both in the
open and closed positions.”
According to information about the stadium provided on its website:
• “The stadium roof may appear to rotate open but it’s an optical illusion, the
roof opens by the movement of eight petals that slide open in a straight line.”
• “Each of the moving petals cantilever approximately 200 feet inwards towards
the center of the stadium and provide a roof covering when the petals are in
the closed position.”
• “The moveable petal structures are powered by eight mechanized ‘bogies’
which drive the petals along an inner rail and are attached to the outer uplift
rail by six roller mechanisms.”
Gus Drosos, HOK vice president/technical principal, says this stadium’s ki-
netic feature could serve as a model for similar projects in the future.
“The owner had a vision. We brought the design, and he saw and embraced it.
I think that’s the key in the future. [Kinetic architecture] has to be a full-on team
effort. The owner has to buy into it; it’s not just a box.”
“I think if we can promote working
together with the subcontractors and
fabricators a little more hand-in-hand
even more phenomenal things can be
accomplished. There are advantages to
the owners as far as it being cost effec-
tive. The software allows us to do more
structures like the Mercedes-Benz Sta-
dium—to not be scared away from
it—and become more integrated with
the delivery of the building. The soft-
ware will be key to iconic buildings of
He adds, though, that a structure like this does come at a premium, so in
order to be successful, there has to be a commitment across the board.
The kinetic part is something with a cost involvement that an owner has to
recognize and it has to be part of the vision to allow the architectural team to pull
it off,” says Drosos. “In this particular case, the owner wanted an iconic building.
Period. He brought us in, understood it and this was herculean and aggressive.
The whole team has to be on the same page to understand what it entails.”
He continues, “And I think it’s phenomenal, seeing what a kinetic structure
can bring to a city, a team and the overall community. There are opportunities
E l l e n R o g e r s is the
editor of USGlass magazine.
Follow her on Twitter @
EllenGRogers and like her on
Facebook at usgellenrogers to
[for more]; there just has to be buy-in from everyone.” n
November 2017 | USGlass, Metal & Glazing