Simulation and evaluation of environmental aspects throughout the design process. J. P. den Hartog A. Koutamanis P. G. Luscuere Faculty of Architecture Delft University of Technology The Netherlands ABSTRACT The evaluation of environmental aspects in architectural design has traditionally been performed by means of simple (and often simplistic) rule systems. These generally remain at the normative level of minimal control one encounters in building rules and regulations, thereby failing to provide sufficient information and clarity for design guidance. Despite this, evaluation results normally bound subsequent design decisions as fundamental, inflexible constraints. At much later design stages, when architectural form has been largely crystallized and when environmental subsystems must be specified in detail, both the architect and the contributing engineers often realize the severe limitation of the initial choices. A frequently voiced argument for such simplification in the guise of abstraction is the lack of detailed information on the form and functional content of a building in the early stages of the design process. This obviously presupposes a tabula rasa generative approach. The application of a priori knowledge in the form of types, cases, precedents and automated recognition permits direct transaction from the abstract to the specific at and between a number of predefined relevant abstraction levels in the representation. The combination of a priori knowledge at the typological level with multilevel representations permits the use of precise simulation techniques already in the early design stages and throughout the design process. The simulation results employ the dual representation principle of scientific visualization, thereby linking form with measurable performance. Feedback from the simulation provides the analysis and evaluation means for design guidance and for communication between the architect and the contributing engineers. A prerequisite to this is that the abstraction level in the representation constrains the analysis derived from the simulation, e.g., by means of grades of fuzziness applied to different zones in the representation on the basis of information specificity. 1. INTRODUCTION: DESIGN AND ANALYSIS In contrast to other design professions, architecture is a discipline where design performance must be judged on many different aspects. Some of these aspects, such as aesthetics and structural integrity, are within the capabilities of most architects. Experience, information and technology provide the means and criteria for assessing aspects like form and stability. Other design aspects are more difficult to predict and often require the assistance of contributing engineers. Consulting these experts at an early design stage is cumbersome and expensive and is consequently often postponed to a later stage.