Design thinking and the precautionary principle : development of a theoretical model complementing preventive judgment for design for sustainability enriched through a study of architectural competitions adopting LEED

This thesis is a contribution to the general theory of design thinking.  In the prevalent demand for a sustainable development, the main objective of this research is the construction of a theoretical model of design thinking that contextualizes standard sustainability evaluation tools. The basis of these normative tools is analyzed in four dimensions: ontological, methodological, epistemological and teleological. Indications of potential counter-productive effects of these norms for design thinking confirm the need for a theory of qualitative judgment. Our central hypothesis revolves around the benefits of the underlying conceptual framework of the ‘precautionary principle’ for design thinking, the first formulations of which goes back to the early seventies in Germany, and was in fact created as a way to address the failures of traditional scientific evaluation tools or methods. The thesis comprises five parts. Beginning with a historical perspective, a review of classical models of design thinking, specifically focuses on the evolving approaches for addressing sustainable development. Theories of “green design” coming from the early sixties, theories of ecological design of the seventies and eighties are finally converging on the developing theories of “sustainable design” formulated in the early nineties.   The underlying theories of the precautionary principle are then reviewed and explored for the specific context of design within the perspective of sustainability.  Current methods of standard risk assessment methods are compared to a precautionary approach, revealing their conceptual limits for design thinking.  A preliminary theoretical model for design thinking is then constructed adopting the theories underlying the precautionary principle. This model represents a global vision for judging the design project in a context of sustainability, rather than on traditional approaches for risk assessment, which are purposive and instrumental.   The precautionary principle is further explored for the specific context of architectural design.  This exploration begins with a historical perspective of the classical notion of ‘prudence’ for guiding architectural judgment. In light of the contemporary issues related to sustainability, we then examine the challenges of judging architectural projects given the increasing international prominence of such standard evaluation methods (i.e. Leadership in Energy and Environmental Design, LEED). The thesis proposes a reinterpretation of design thinking as proposed by Donald A. Schön is introduced such that the use of tools, like LEED can be contextualized. This exercise reveals an epistemological barrier, which shall be taken into consideration when reformulating the theoretical model.  In accordance with a constructivist epistemology, a new theoretical model is therefore confronted to the study and illustration of three contemporary Canadian architectural competitions adopting the standard evaluation method LEED. A preliminary set of ‘tensions’ identified in the judgment process and design thinking is further categorized into their conceptual counterparts. These are: (1) analogical/logical conceptualization; (2) epistemological/methodological uncertainty; (3) interpretive/analytic comparability; and (4) universal/contextual relevance of the proposal. These conceptual tensions are considered as vectors that come into correlation with the theoretical model, enriching it, yet without validating it, in the positivist sense of the word. These confrontations with the real, help better define the epistemological barrier identified above.  This thesis therefore highlights the often underestimated impact of environmental standards on the judgment process and design thinking, with particular, albeit non restrictive, reference to contemporary Canadian architectural competitions for public buildings. It concludes by stressing the need for a new form of “reflective prudence” in design thinking along with a more critical use of current evaluation tools for sustainability founded on a global integration rather than on the opposition of environmental approaches.

Keyphrases: design thinking, sustainability, precautionary principle, prevention, judgment, reflection-in-action, technical rationality, complexity, systemic, architectural competitions, LEED