New Urban Forms, Diversity, and Computational Design: Exploring the Open Block

Abstract

Architects, urban designers, and city planners witness a contemporary lack of imagination regarding new urban form typologies. Most proposals have swung between two well-defined extremes: the dense, traditional block and the strips/towers defined by the modernist principles. More recent yet distinctive proposals are rare, even as the challenges of urban environments have changed. Based on the concept of diversity, one notably acclaimed exception is Christian de Portzamparc's open block (îlot ouvert), proposed as a set of flexible, interdependent rules that ensures an attractive, varied urban scene, and applied in Masséna, a new neighborhood in Paris. However, this new typology has raised some issues, such as the necessary design efforts or the developer's uncertainties as to buildable surface associated with flexibility of form. Computational design tools (CDT) provide an opportunity to explore and quantify the performance and limits of new urban form typologies. Using CDT, this study first confirmed that the rules stated by Portzamparc were sufficient and consistent to achieve the intended urban forms, and that these forms are translatable into common design code parameters. Second, this study discussed the open block as a new form type, by framing its degree of diversity. Finally, this study checked the utility of CDT during the decision-support process and concluded its potentially wider convenience to explore renewed morphological creativity in urban designers beyond rigid design codes and standards.