I met Andrés almost 20 years ago in our first collaboration with him on a housing project in Majadahonda. I was warned that Andrés would be hard, demanding, and not very receptive to reticence or objections. They had not been mistaken, nor exaggerated in their warnings. Andrés is a firm defender of his ideas and objectives, but what they failed to add, was that he is also a lover of reasoned discussions, especially of structures, which is one of his passions (I wouldn't say hidden).
That confrontation that was supposed to end with my bones on the canvas became the first of innumerable "confrontations" from which we have enjoyed so much since that date. For some reason that I don't quite understand, Andrés trusted me from day one. Even less so if we put into context the 34 years of age that separates us and that Andrés was an established architect with buildings executed with highly complex structures solved by top-level structural engineering teams.
It has never been clear to me if it was premeditated, but that confidence in Andres was always a double-edged sword for me. Yes, I had his trust, but I had to answer for it. I never had Andrés as a teacher, but I can affirm that nobody made me study so much.

Fontán building by Andrés Perea, Elena Suárez, Rafael Torrelo. Photograph courtesy of AP+ES+RT.
After that first project came many more, and always with Andrés wanting to advance in structural concepts that did not stop approaching his head. The achievements of the previous project were already a reality that he incorporated into his new projects, regardless of the complexity involved, and always looking to add something more, and without joints, of course.
If I stick to the structural design of Andrés Perea, for those who know his architectural work, it would be necessary to highlight a series of elements and concepts that I believe are a constant in his practice.
First, the slenderness or, to be more precise, the search for beauty through slenderness. I understand that it is a God that many architects worship, but Andrés takes it to its ultimate consequences. And in that search, he found the massive circular pillars. I still remember the first time he taught me about their use.
That confrontation that was supposed to end with my bones on the canvas became the first of innumerable "confrontations" from which we have enjoyed so much since that date. For some reason that I don't quite understand, Andrés trusted me from day one. Even less so if we put into context the 34 years of age that separates us and that Andrés was an established architect with buildings executed with highly complex structures solved by top-level structural engineering teams.
It has never been clear to me if it was premeditated, but that confidence in Andres was always a double-edged sword for me. Yes, I had his trust, but I had to answer for it. I never had Andrés as a teacher, but I can affirm that nobody made me study so much.

Fontán building by Andrés Perea, Elena Suárez, Rafael Torrelo. Photograph courtesy of AP+ES+RT.
After that first project came many more, and always with Andrés wanting to advance in structural concepts that did not stop approaching his head. The achievements of the previous project were already a reality that he incorporated into his new projects, regardless of the complexity involved, and always looking to add something more, and without joints, of course.
If I stick to the structural design of Andrés Perea, for those who know his architectural work, it would be necessary to highlight a series of elements and concepts that I believe are a constant in his practice.
First, the slenderness or, to be more precise, the search for beauty through slenderness. I understand that it is a God that many architects worship, but Andrés takes it to its ultimate consequences. And in that search, he found the massive circular pillars. I still remember the first time he taught me about their use.
"You put as many as you need depending on the axles they have, but I don't want them to have a diameter greater than 150 mm".
And so it was. I have lost count of all the ones I have designed with him, but after so much time, one gets fond of what we in our team call "Perea Pillars".

Fontán building by Andrés Perea, Elena Suárez, Rafael Torrelo. Photograph courtesy of AP+ES+RT.
What at first seemed an inconvenience, soon became an unexpected asset, if you knew how to use it. These are elements with a high vertical load capacity, but very little stiffness and therefore, little capacity to take horizontal forces. But we are talking about projects where there are no joints, where the horizontal deformations due to temperature and shrinkage hit the end columns. Unless they have low stiffness, so there you have the beauty!
I'm not sure which came first, the jointless buildings or the "Perea Pillars", but both were certainly created to share the same stage.
I think we have enjoyed all these years of small discoveries like this one, which showed us the way to future ideas and forms, and which have filled many hours of structural discussions. Like when we designed the roof of IFEMA's Pavilion 12, a 120 m span cable-stayed roof resolved with mullions supported by asymmetrical suspenders anchored in a large compression ring, which made us enjoy and suffer like no other.

Fontán building by Andrés Perea, Elena Suárez, Rafael Torrelo. Photograph courtesy of AP+ES+RT.
Secondly, I should mention "structural logic". In short, the position, dimensions, and section of the elements of the building respond to a structural motivation that allows the observer to understand the resistant operation, in addition to admiring how the rational use of it inevitably derives in the fulfillment of the primary objective of achieving slenderness and beauty.
Thus, in the IFEMA parking lots, the position of the columns, spans, and overhangs was fixed only by structural criteria to achieve compensation of moments that would allow reducing as much as possible the edge of the slab, and on the other hand, ensure a centering of loads to execute the parking lot with solid circular columns of 150 mm diameter articulated at its base.
And lastly, and it escaped me before, his obsession with eliminating expansion joints. Yes, that simple division into blocks of a building to release the temperature and shrinkage stress that we engineers love so much for everything that simplifies our work and that for Andres is like salt in a wound. God, what a pain!!! But there is nothing to be done. Don't try. Andres does not make gaskets, and that's it.
But I don't want to deviate from the reason for these letters: the Fontán Building Project.
From the point of view of structural design, the project stands out for three main milestones. The first, and perhaps the most relevant, was to undertake a remodeling that had to respect the existing structure, being necessary to add one more floor and over it a general roof that would cover the different areas in a way that would somehow maintain the general concept used in the City of Culture, respecting the original shape of Mount Gayas. In addition, since a building was designed for a use that was antagonistic to the initial one, it was necessary to have large openings that would allow light to enter the different spaces.

Fontán building by Andrés Perea, Elena Suárez, Rafael Torrelo. Photograph courtesy of AP+ES+RT.
The project began with countless studies of stresses in openings to determine the points where the openings were to be placed to maintain as much as possible the laws of bending moments of the existing structure and make it possible to reuse the structure without the need for reinforcements, so forbidden for economic reasons.
On the other hand, these openings had to compensate for the load increase that was produced in the columns by the addition of a floor plus the roof, as required by the building. From the outset, this study meant that the geometry of the building's ground floor depended on a factor external to the purely architectural one, in which Andrés' projects are so fond of moving. There you have a sample of the search for "structural logic."
The second milestone, in my opinion, I would say was Andres' need to make the building "his own." I was very skeptical about the result of introducing a foreign body in all that ordered and mathematical body that the City of Culture represents, but Andrés materialized its most representative elements in an almost natural way ("Perea Pillars" included,) while we applied the same concepts shared in previous projects in an almost instinctive way. It's a creative process that you end up getting hooked on. Andrés always lets you propose, and so much so, that I would say that I can recognize my fingerprint in countless elements of all the buildings we have shared.

Fontán building by Andrés Perea, Elena Suárez, Rafael Torrelo. Photograph by Manuel G. Vicente.

Fontán building by Andrés Perea, Elena Suárez, Rafael Torrelo. Photograph by Manuel G. Vicente.
As a result of this instinctive exercise, I would cite the third milestone, the roof of the building.
The starting point, I think I remember, was Andrés's demand that the roof should have longitudinal raised lines that were the only family of structural elements of the roof, and that these should be marked externally, directly supporting a collaborating deck. First idea, and we were already getting complicated. As so many times, the design was born from a structural requirement.
We were starting from a structural mesh of the existing building of 8 x 8m, and the collaborating slabs only allow spans of 4m, so I made him see that his proposal could not be executed. And like a beginner who had never faced Andrés, I added... "unless we had main longitudinal beams every 4m, offset 2m from the column alignments supported by inclined columns with top suspenders or with powerful cantilevers," like someone who offers a crazy solution that he assumes his interlocutor will reject, reaffirm the impossibility of his first statement that there was no solution to the proposed problem. The result can be seen by anyone who wants to visit it.
It is fair to say that the collaboration with Elena and Rafa would deserve a similar amount of letters because of the long relationship that links me to both (my first project was with Rafa, just to give a fact), and for hundreds of meetings, discussions, and good times lived in the design of this great building started from an early abandoned apathy, and that, in case anyone is wondering, has no joints either.
Text by Ignacio López Picasso.