The Princeton Envelope Group (PEG) is a design and research unit at the Princeton University School of Architecture. Headed by Alejandro Zaera-Polo and coordinated by Urtzi Grau. The unit is engaged in a three year research program on the Politics of the Building Envelope the conclusions of which will be published in a forthcoming book by Actar Press, Barcelona+New York.


The relationship between material organizations and their notation of their forms of communication has shaped the history of the discipline. The Greeks used to equate form and idea, but this identity has been mediated in several forms since. There are multiple possibilities in the regimes of signification applicable to architecture. Charles S. Peirce’s Vital classification on icons, indexes and diagrams is relevant to the discussion and interesting to consider here.

Most recently and after a few decades in which the architectural debate was focused on semiotics, representation and language, there has been a turn towards methodology and instrumentality, putting into question some of the ore traditional mechanisms of architectural representation. Globalization and the resulting process of cultural hybridization requires architectural practices capable of building spatial and material organizations that transcend univocal cultural constructs. Within this environment practices that rely on cultural conventions become dependent on a certain level of consensus and cultural consistency which is no longer a default condition within contemporary advanced social structures. The search for a priori cultural or political effects may not be effective in this emerging urban environment. Design practices may devise methods to generate coherent non-representational forms that lend themselves to affiliative relationships a posteriori, generating projective arguments rather than interpreting, mimicking or representing existing ones. The development of information technologies has triggered practices that are more driven to the production of new realities than to the representation or interpretation of an existing one.

As opposed to signifying or symbolic operations, diagrammatic practices have become a key subject of the contemporary architectural debate, and are capable to produce organizations with multiple political performances. It is therefore important to clarify the terms of discussion in order to understand how the diagram relates to other instruments and mediations between concepts, material organizations and effects.

If the origins of the diagrammatic practices in the 1960’s tend to avoid the iconic similarities between the diagram and the building, some of the Pop-based architects would resort to icons and signs as a way of drawing relationships between concepts and form. Some of the architectural proposals that emerged in the 1970’s within critical practices were primarily aimed to produce mediations between cultural or subjective representations through abstract formal systems as an alienating mechanism, practicing a sort of dialectical materialism aimed at de-stabilizing the status quo. The project of autonomy and the utopian approaches dating back from the 1970’s belong to this lineage where the world evolves through the dialectic between the real and the utopian. The diagram traces the virtual, sometimes on the level of the organization of space and matter, sometimes to the production of sensations and affects.