First in Fashion
New Glazing Trend Sets the Stage for Future
by Ellen Rogers
Sometimes it’s the simplest of ideas, designs, fashions and trends that
make the biggest statements. Think Audrey Hepburn circa “Breakfast at
Tiffany’s.” To this day few items make as much of a fashion statement
as a simple black dress and a few strands of pearls. And a simple, yet
memorable statement, was exactly what the Spanish architectural firm of
Rafael de La-Hoz was going for when it designed the new facade for the
home of Inditex, the company behind fashion brands such as Zara, Pull
& Bear and Massimo Dutti, located at Castellana 79 in Madrid, Spain.
“We were looking for an abstract and plain composition for the façade
that wouldn’t penalize the view from the inside because of the façade
‘character,’” says design architect Francisco Arévalo. “The client’s
request was to have a singular building, but discreet at the same time,
with an impeccable function as an office.”
Glass and glazing materials played a key role in bringing this architectural
creation to life. Arévalo says they looked to the squares of a
chessboard as the design inspiration, while also incorporating a double
skin to provide natural daylight penetration.
“This resulted in a neutral, abstract and plain façade, but at
the same time [one that is] alive, with volume.”
Setting the Stage
When it came to the early stages of the design process, Arévalo
says the location of the building within the city posed a challenge.
“Located next to one of the best office towers in the country of one of
the great masters of 20th century Spanish architecture—Francisco Saenz
de Oíza—[the location] raised the idea of respecting the past,
yet being able to differentiate our styles from the rest of the buildings
without much architectural show-off,” says Arévalo. “We could not
compete with the Banco de Bilbao Tower in height (it stands 107 meters)
nor the location, but we [also did not want to] merge with it.”
He continues, “These urban premises and the client’s requests to have
a singular, but at the same time, discreet building, conditioned the concept
of the project from the very first moment.”
So when designing this new office building, Arévalo says a number
of components came into play. These included not only the aesthetic, but
also the performance features.
“Because it was the first time
being used in an exterior project, the testing was the biggest hurdle
to overcome. Once that was completed the fabricators could move forward
comfortably. Testing was paramount to the whole process.”
—Peter Katcha, Sefar
“From our experience, especially with office buildings in
Madrid, having a double skin façade helps the interior comfort,
both acoustically and thermally, so we considered this façade solution
from the very first moment,” he says. “The building location, in one of
the great thoroughfares of the city and the south orientation, also advised
But there was also the aesthetic appeal—the checkerboard appearance—and
the question arose as to just how to make such a look work, while still
ensuring the views of the outside from within.
“We searched all sorts of glass treatments: silkscreen with different
degrees of opacity and color, [acid] treatments, sandblasting, [working]
with different colored sheets of butyrals, but all of them affected the
view from the inside,” says Arévalo.
Then there was the idea of incorporating a metal mesh. Arévalo
explains that on many other projects his firm has worked with companies
that specialize in laminated glass with metal meshes, but the concept
never worked well. For example, a true metal mesh can come with a high
price tag, for one, and also add weight to the glass, making it difficult
to work with and install. Other reasons he says such previous materials
were unsuccessful include the fact that they had either not passed testing
requirements for use on façades or did not meet their architectural
Already working with DuPont’s SentryGlas laminated glass products, the
architectural team soon learned of a product called Sefar Vision, which
is an alternative to traditional metal mesh; it’s a metal-coated fabric
interlayer, typically laminated within glass or other transparent materials.
Peter Katcha, director of North American sales with Sefar, says that while
double-skin facades are popular in Europe, creating one with just a laminated
glass product does not provide much of an aesthetic, and the aesthetic
feature was something architects were looking to capture.
“[DuPont] introduced [to architects] Sefar Vision in combination with
SentryGlas, which provides a nice aesthetic, an almost 3D appearance to
the façade,” says Katcha.
While Arévalo says he was interested in working with the Vision
product, there was a challenge: at the time it was not approved for use
with glass in an exterior façade in Spain.
“We had samples of laminated glass with metallic interlayers
and Sefar meshes in the office, but none of them could be used at that
time outdoors,” he says. “We got in touch with official Sefar suppliers
in Spain and after several negotiations we reached the [opportunity] to
use it, since it was already in testing and standardization processes
in our country and [and would be ready in time to meet] construction dates.”
Katcha says his company worked closely with DuPont on a battery of tests
to ensure the product would work in exterior applications, as previously
it had only been used in interior applications. This testing procedure
included those for adhesion, edge stability, high temperature resistance,
high moisture resistance and lightfastness.
“It was that testing that made it possible to use Sefar Vision in this
project,” says Katcha. “Because it was the first time being used in an
exterior project, the testing was the biggest hurdle to overcome. Once
that was completed the fabricators could move forward comfortably. Testing
was paramount to the whole process.”
The resulting project features a glass curtainwall created to resemble
a three-dimensional checkerboard with alternating panels of clear laminated
glass and panels embedded with the mesh product. Each panel is approximately
11.2- by-6.4 feet and consists of two layers of 8-mm, low-iron tempered
glass laminated with .52-mm SentryGlas. The reflective aluminum coating
allows the façade to come alive with depth and light refraction
that mirrors the changing outdoor conditions of the sun and clouds. From
the inside, building occupants have an unobstructed view of the outside.
The glazing systems reduce glare from the sun and reflect the warmth away
from the building, helping reduce the need for air conditioning.
A number of companies were involved in the fabrication, all of which took
place in Spain. The glass was cut and polished by Vitro and Cricursa did
the lamination. The Spanish firm Caamaño and Metalvedro served
as the installers and assemblers of the façade.
“From our experience, especially
with office buildings in Madrid, having a double-skin façade
helps the interior comfort, both acoustically and thermally, so we considered
this façade solution from the very first moment.”
Rafael de La-Hoz
Since the project was the first to use the Vision product in an exterior
application, and considering the necessary approval and testing, Arévalo
stresses that a “very direct and intense collaboration with both the supplier
and installer” was critical.
Katcha agrees that communication was important.
“Working together was important to make sure everyone would be confident
in ensuring the design concept could be realized,” Katcha adds.
True to Form
Aside from being the first project to incorporate the mesh product in
an exterior application, Arévalo says there are some other details
about this project that make it unique.
“The ‘rehabilitation’ part, where we had to respect the existing steel
columns of the previous building, demolish all the floors and walls and
reinforce the foundations of ancient buildings was a challenge, but a
successful one,” he says. Speaking of the architectural details and features
found within the city of Madrid itself, he adds, “Being able to offer
both our client and the city a simple design [that’s also] full of expression
and nuance in one of Madrid´s most populated districts [was a great
learning experience].” AG
Ellen Rogers is the editor of the Architects’ Guide to Glass &
Metal magazine. She can be reached at email@example.com
or follow her on Twitter @AGGmagazine and like AGG magazine on Facebook
to receive updates.
Architects' Guide to Glass & Metal
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