The siamese towers

Architects:
Alejandro Aravena, Charles Murray, Alfonso Montero, Ricardo Torrejón.
Project:
2003 - 2004.
Construction:
2004 - 2005.
Built
Area: 5000 m2.
Budget:
US$ 400 x m2.

We were asked to build a glass tower to host everything that had to do
with computers in the university.
We saw 3 problems in this: the computers, the glass and the tower.

The university asked us to question the type of architecture required
for teaching now that everything depends on digital technology. Should architecture
change now that we have computers? Does the notion of room (be it for work or
for attend a class) still make sense?
Our answer was, of course, Yes and No.
Yes, because the paradigm for working spaces has been reversed; if until
now a good room, was the one that had a good natural light (library, classroom,
etc), now that we work on screens, a good space is the one that has achieved a
good half-light (to avoid uncomfortable reflections). This fact led us to
explore a relatively hermetic volume, with very controlled perforations towards
the outside.
But on the other hand, we were not that optimistic regarding computers
and their influence in education, or the transmission of knowledge; in the end
nothing will defeat a good conversation of two persons (be it between a
professor and a student, or between students) under a good shadow, drinking a
nice cup of coffee or having a casual conversation in a corridor. (We had in
mind Louis Kahn’s old notion of institution in this case that of a school). In a
way, formal education is taken care by building codes: light, acoustics,
ventilation, etc. but nobody takes care of informal education and there we saw
a design opportunity. So, instead
of moving forward thinking about the next step in education, we thought we had
to move back as much as possible, to more archaic and primitive ways of being.
Wood slopes, a natural public bench, or a 10 storey high corridor were those
spaces where we expected old good conversations to take place.

Regarding the glass, the problem was that building a glass tower in
Santiago, means automatically to take care of the greenhouse effect. We had no
money for a curtain-wall, able to solve all the issues in 1 single skin
(double, reflective and colored glass). Even if we had the money, the amount of
energy that has to be spend afterwards for air conditioning is obscene. Finally
we did not like mirror glass for the façade, because it is vulgar.
So instead of thinking about a skin capable of doing all the job
(protection against dust, rain, smog, weathering and greenhouse effect) which
costs around US$120 x m2, we thought that it would be cheaper to do
several skins, each of them doing well 1 thing at a time. So we designed an
outer single glass skin, very bad in energetic terms, but very good against
weathering and then an internal building made out of fiber-cement, bad against
weathering but energetic wise. In between them: air. All we had to do, was to
avoid the greenhouse effect generated after the sun trespassed the glass, before
it reached the second building inside. So, we allowed the space in between the
2 buildings to perform as a perimeter chimney, letting the hot air to leave the
system, ascending by convection to a void in the top. A constant and natural
vertical wind, helped by the Venturi effect created by the waists will
eliminate the greenhouse effect. The sum of the two buildings, because they
were more specific in their performances, was 30% cheaper . We also expect to
spend much less energy during it’s
useful life.

Finally, there was the problem of trying to have a tower, because we had
just 5000 m2 to achieve it. Didn’t matter how much we reduced the
surface of each floor, the resulting figure was pretty chubby; it was a high
building, but it didn’t look like a tower. So the only solution we thought of,
was to cut the volume in two from the 7th floor up. For each of the
resulting parts we used almost width-less aluminum pieces of slight different
colors. So if seen from the front, the building was a unique bi-chepalus
volume, but seen as a foreshortened figure, the color difference could show a
couple of really vertical figures, that happened to share great part of their
bodies, as if they were Siamese creatures.