On Line: Álvaro Siza’s Cadernos Pretos

Peter Testa on the Álvaro Siza fonds
Find and Tell, November 2018

The CCA recently received the Álvaro Siza archive, which contains some 300 of Siza’s over 500 cadernos pretos—or black notebooks. Drawing has always been Siza’s primary representational medium, but until now his sketches have not been viewed and studied in their proper context within Siza’s vast output of notebooks and project documentation. This is one of the largest collections of exploratory drawings by any architect in the history of the discipline; its significance parallels that of Le Corbusier’s carnets and Aldo Rossi’s quaderni azzurri.

The CCA’s Siza cadernos contain more than 24,000 pages of drawings, annotations, and texts—conversations with projects, people, places, and animals. There is spontaneity and an uncanny consistency in the generic notebooks (A4, soft cover, stapled, unlined) in which Siza invariably marks only the right-hand pages of nearly-transparent paper with a black disposable Bic pen. The symmetry between their generic format and exceptional content is consistent with Siza’s speculative posture.


Architectural drawings tend to follow rules with respect to types and combinations of drawings. There is the assumption that the plan, section, and elevation will be read against each other and that the perspectives illustrate preferred views. Architectural sketchbooks tend to follow rules, too—there is the expectation they will be read sequentially with some sense of progress of generating, discovering, solving, and building up the detail of a project. Siza’s cadernos are not governed by either set of conventions; viewed in their entirety, the notebooks make apparent a precise deviation from architectural norms.

On the pages of the cadernos, Siza’s signature drawing style develops a particular formal logic. His line weight does not vary, shadow rarely appears, and color is absent. An attitude toward latent multiplicity in perception is evident as multiple views of either the same object or of multiple objects occupy the same page. He turns things into objects through repeated drawing, positioning, and scaling. In the cadernos, there is no object classification—bodies, buildings, and cities arrange themselves together. For the most part, objects have clearly delineated edges—there is a sense of outline and profile with little texture or fill. The cadernos confound any singular subjectivity by placing recognizable views of architectural objects alongside impossible views of those same objects. As a result, the drawings confer an “objecthood” upon projects—it is as if they are fully-known three-dimensional entities, rotated in space and captured in the notebooks.


Most compellingly, the cadernos document inquiry into the form of things. Siza’s constant, unrelentingly iterative practice of drawing allows him to render familiar objects as abstract. Arguably, the author cares less about the objects themselves than about their relations; their compositional structure is what matters. The cadernos are the means by which Siza explores the syntax of architectural objects, known or new, real or imagined. On the pages of the cadernos, syntactical operations become a way for architecture to talk to itself.

Rather than a subjective representation or attempt at an accurate expression of reality, the cadernos indicate a more rigorous realism that apprehends the real beyond thought and individual experience. They treat all things as legitimate with equal right to poetic existence—almost anything can appear at any moment. As Siza notes on a drawing made at the Piazza Navona in Rome dated April 1981, Nada selecionar - Tudo e realidade (Nothing to select—Everything is reality).


The CCA’s Siza archive begins with documentation of projects for the 1979 Internationale Bauausstellung (IBA) exhibition competition in Berlin, an urban renewal strategy that solicited housing proposals by international architects. The Berlin cadernos evidence a shift; whereas a relational strategy generates architectural objects in earlier works like the Banco Pinto & Sotto Mayor (built), in the work from the 1980s and later, the qualities of the architectural objects themselves produce relations between or among objects. Beginning with the drawings for Siza’s Fraenkelufer project (unbuilt), architectural objects have intensive and extensive relations; they are shown being-alone and being-in-relation with one another.

The drawings affiliated with the urban projects Fraenkelufer, Schlesisches Tor (Bonjour Tristesse) (built), and Kottbusser Damm (unbuilt) highlight the inherent, typological objecthood of the perimeter block as composed of quasi-autonomous, though repeated objects. In the Fraenkelufer drawings, the presence of solitary objects at the interior of the block juxtaposes their absence at the perimeter. Buildings are shown in the round; multiple views of single architectural objects and multiple views of multiple architectural objects occupy the same page, drawn and positioned a-sequentially. View and object achieve parity: equality but not equivalence.

Álvaro Siza. Spread from Sketchbook 46, December 1979. Álvaro Siza fonds, CCA. AP178.S2.046.084-085

The discontinuous unity achieved in these projects proposes a novel coherence—a non-unitary relation that is neither figure/ground nor collage. This ontological shift in Siza’s architectural research program coincides with a broader disciplinary preoccupation with the city as premise and context of the architectural object. This preoccupation characterizes projects contemporaneous to Siza’s Berlin projects; it is notable in the work of Aldo Rossi, James Stirling, John Hejduk, and Peter Eisenman. Furthermore, among the many architects who took on schemes for the IBA, only Siza and Hejduk avoid simply reconstructing the perimeter block, instead treating Kreuzberg as an opportunity to manifest new architectural figures, urban forms, and narratives.

Álvaro Siza. Spread from Sketchbook 55, May 1980. Álvaro Siza fonds, CCA. AP178.S2.055.a

Álvaro Siza. Spread from Sketchbook 94, October 1981. Álvaro Siza fonds, CCA. AP178.S2.094.d


The conceptual consequences of the multiple and the positioning of object against relation govern the cadernos from the Berlin projects onwards. Alongside a rigorously austere formal language, Siza develops a compositional aesthetics that considers “multiple” as “many” and as “copy.” The cadernos reveal an interest in recurring pieces that make up a repertoire of forms from which future projects emerge. Besides contour and displacement, the strategies of pairing, multiplying, and repurposing appear in drawings for the Two Houses and Two Shops in Van der Venne Park (built), the Faculty of Architecture at the University of Porto (built), and the juxtaposition and superposition of systems and objects appear in drawings of the Iberê Camargo Foundation Museum (built).

Álvaro Siza. Spread from Sketchbook 201, April 1985. Álvaro Siza fonds, CCA. AP178.S2.201.d

Within the collection of overseas works at the CCA, the Two Houses and Two Shops in Van der Venne Park in the Hague is an architectural diptych that stages Siza’s capacity to bring seemingly disparate objects into new compositions. The cadernos devoted to this work are overflowing with drawings that explore the use of profile as a way of presenting two things as if they were alone together. Siza’s drawing strategies become architectural strategies—outline and negative space, as techniques of drawing, organize the architecture and direct its reading. These drawings pose an architectural body that is never at rest by continuously redefining its outline. The placement of objects suggests that they have been turned or over-turned, somehow unsettled from an original or natural position. In plan, each object shares an edge with their constructed socle and deviates on all the other sides from the ground’s boundary, prompting a viewer to mentally turn the object in an attempt to achieve an original fit—an analog to the representational turning-in-space of the architectural object found in earlier notebooks. Siza’s line as geometry, contour, and profile thus merges the tectonic and the topological.

Álvaro Siza. Spread from Sketchbook 208, August 1985. Álvaro Siza fonds, CCA. AP178.S2.208.j

Álvaro Siza. Spread from Sketchbook 210, May 1985. Álvaro Siza fonds, CCA. AP178.S2.210.092-093

Álvaro Siza. Spread from Sketchbook 213, November 1985. Álvaro Siza fonds, CCA. AP178.S2.213.d

Borrowing from the two formal drives of Dutch modernism—the rationalism of the Rotterdam school and expressionism of the Amsterdam school—Siza’s Two Houses and Two Shops attain an alien quality, appearing at times real and at times a representation. Put to work in the same space, the conventions of each school neither contradict nor support the other, but rather establish a simultaneous and equivalent estrangement through a process of de-semantification. At once cultural and artistic, the Two Houses and Two Shops posit the possibility of a purely aesthetic means of relation.


Álvaro Siza. Spread from Sketchbook 257, August 1987. Álvaro Siza fonds, CCA. AP178.S2.257.074-075

After the Hague projects, Siza expands his representational aesthetics of multiple non-correlated objects in the Faculty of Architecture building at the University of Porto campus. Like the Two Houses and Two Shops in Van Der Venne Park (which reappear as if copy-pasted in drawing AP178.S2.257.075 as the “gate house” to the Faculty), this ten-building campus suggests several architectural types not usually seen together. The Faculty of Architecture posits a coexistence of typologically unrelated buildings, from its baroque enchainment of institutional spaces that form a boundary to the north to its neo-classical and modernist studio pavilions overlooking the Douro River. In the cadernos, it is not each thing separately but all things separately that form a whole understanding of individual yet not isolated types.

The effect of multiple objects and views on the same page is particularly evident in the Faculty of Architecture drawings. Each drawn instance can be read as a “view” of an architectural object already represented elsewhere on the page (i.e., the object is “turned” and viewed multiple times) or as a single instance of one architectural object among many (i.e., there is one view of many objects), making it impossible to discern a narrative of versioning. To play each architectural object against the idea of type, Siza engages a non-correlation of parts without blending, deforming, mixing, or translating. He challenges each object’s gestalt not by fragmentation but by copying, duplicating, and multiplying. Finally, despite a process of so many parts, Siza always transforms complexity into laconic architectural solutions.

Álvaro Siza. Spread from Sketchbook 248, May 1987. Álvaro Siza fonds, CCA. AP178.S2.248.c

Álvaro Siza. Spread from Sketchbook 260, September 1987. Álvaro Siza fonds, CCA. AP178.S2.260.b


In the Faculty of Architecture cadernos, as in the archive as a whole, Siza sketches both buildings and bodies. While not part of an anthropomorphic tradition that projects an organic human body onto inorganic urban or architectural material, the figural drawings dispersed throughout the cadernos evidence a non-metaphysical affirmation of the body. Presumed wholes are separated into parts and re-constructed through jointing and socketing. The cadernos give access to worlds in which the qualities that traditionally govern the plausibility of physical adjacencies—view and scale (human and non-human)—are subverted in service of re-seeing.


The process by which object and relation achieve parity reaches its pinnacle in the Iberê Camargo Foundation (1998-2008), a museum set within a former quarry facing the Guaiba River estuary in Porto Alegre, Brazil. The project establishes a surreal alliance of the two ordering systems that organize the colonial cities of South America: a Cartesian grid structures the galleries, and a topographically-inspired network of local negotiations comprises bifurcated ramps that provide the building’s primary circulation. These ordering-systems-as-objects are architectural beyond their image. They are neither inscribed in the ground nor diagrams of movement made physical; rather, their ordering is spatial, experiential, and consequential for the occupation of the building.

The Iberê Camargo drawings are unusual for their insistence on a single view. Here, the project is drawn many times from the same position as if impossible to imagine from behind the mountain against which it sits. This imposed stillness gives access to a new reading of “multiple”—in the Iberê Camargo there is a nested and layered multiplicity found within a single object. In this drawing series, the specific quality of Siza’s line work is especially striking for its suggestion that, rather than sketching a projected reality, Siza is in fact recording something immanent. These cadernos are filled with objects seemingly drawn from memory and not as if they were designed, strictly speaking, on the page.

Most clearly of all the notebooks, the Iberê Camargo cadernos reveal that the drawing as a prefiguration of the building is a fiction in Siza’s work. With respect to both the drawings and the architecture, representation enacts the revelation of objecthood. While they contain recognizably architectural parts and operate within cultural and disciplinary traditions, the cadernos convey a subtle yet pervasive sense that the built work aspires to the ambiguous and evasive qualities of his line drawings. Each building is itself a kind of representational object that avoids traditional distinctions between the material and the immaterial.

In spite of its apparent solidity, the Iberê Camargo exists at the edge of perception; it is neither there nor not there. The visual regimes employed in the cadernos and the suppression of extraneous detail in the built work equally determine this fugitive quality. Without openings to measure against, there is no conventional exterior and interior, and its massing is scaleless and indefinite. The building is all threshold—literally, the interiority of the project is just as often projected outward as it is gathered inside. The Iberê Camargo instills a pervasive ambivalence; both the building and the experience of its drawings are fundamentally in-between: material-immaterial, being-becoming, thing-idea.

Siza’s Heresy

Siza’s disciplinary heresy involves an equivocal exchange of one representational form (architecture) for another (drawing). In every Siza project, this ambiguous quality is the inversion and apotheosis of Alberti’s theory of disegno, which positions the architect’s territory squarely within the medium of drawing and requires an absolute minimum of difference between the drawn work and its built counterpart. Siza’s work turns this diagram on its head. With the discovery of such a contradictory position in the cadernos, Siza’s oeuvre can be reconsidered as a collection in which the humanist project of situated materiality coexists with the post-humanist project of representation.

Peter Testa was in residence at CCA in April 2018 as part of Find and Tell, a program that promotes new readings that highlight the intellectual relevance of particular aspects of our collection today.

The CCA shares the archive of Álvaro Siza with the Calouste Gulbenkian Museum and Serralves Foundation.

Digitized sketchbooks in this essay

Related residency


Sign up to get news from us

Email address
First name
Last name
By signing up you agree to receive our newsletter and communications about CCA activities. You can unsubscribe at any time. For more information, consult our privacy policy or contact us.

Thank you for signing up. You'll begin to receive emails from us shortly.

We’re not able to update your preferences at the moment. Please try again later.

You’ve already subscribed with this email address. If you’d like to subscribe with another, please try again.

This email was permanently deleted from our database. If you’d like to resubscribe with this email, please contact us

Please complete the form below to buy:
[Title of the book, authors]
ISBN: [ISBN of the book]
Price [Price of book]

First name
Last name
Address (line 1)
Address (line 2) (optional)
Postal code
Email address
Phone (day) (optional)

Thank you for placing an order. We will contact you shortly.

We’re not able to process your request at the moment. Please try again later.

Folder ()

Your folder is empty.

Please complete this form to make a request for consultation. A copy of this list will also be forwarded to you.

Your contact information
First name:
Last name:
Phone number:
Notes (optional):
We will contact you to set up an appointment. Please keep in mind that your consultation date will be based on the type of material you wish to study. To prepare your visit, we'll need:
  • — At least 2 weeks for primary sources (prints and drawings, photographs, archival documents, etc.)
  • — At least 48 hours for secondary sources (books, periodicals, vertical files, etc.)