Citation: Gradišar, L.; Klinc, R.; Turk, Ž.; Dolenc, M. Generative Design Methodology and Framework Exploiting Designer-Algorithm Synergies. Buildings 2022, 12, 2194. https://doi.org/10.3390/ buildings12122194 Academic Editors: Yuan Chen, Xianfei Yin, Bo Xiao, Yinghua Shen and Hexu Liu Received: 19 October 2022 Accepted: 8 December 2022 Published: 12 December 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). buildings Article Generative Design Methodology and Framework Exploiting Designer-Algorithm Synergies Luka Gradišar * , Robert Klinc , Žiga Turk and Matevž Dolenc Faculty of Civil and Geodetic Engineering, University of Ljubljana, Jamova 2, 1000 Ljubljana, Slovenia * Correspondence: luka.gradisar@fgg.uni-lj.si Abstract: Designing is a problem-solving activity. The process is usually iterative: a solution is proposed, then analysed and tested until it satisfies all constraints and best fulfils the criteria. Usually, a designer proposes a solution based on intuition, experience, and knowledge. However, this does not work for problems they are facing for the first time. An alternative approach is generative design, where the designer focuses on iteratively defining a problem with its constraints and criteria in the form of a parametric computational model, and then leaves the search for the solution to the algorithms and their ability to rapidly generate and test several alternatives. The result of this approach is not only a set of solutions embedding implicitly the knowledge but also a model where problem-defining knowledge is quite explicit. The idea of the proposed approach is the exploitation of synergies between the designer and the algorithms. The designer focuses on problem definition and the algorithm focuses on finding a solution, showing that the capacity of the generative approach to replace the designer is limited. In the paper, we first present the framework of generative design, then apply the process to a case study of designing an efficient shading solution, and in the end, we present the results and compare them with the traditional approach. The approach is general and can be applied in other areas of engineering. It is relevant both to designers as well as software developers who are expected to take this approach further. More theoretical work is needed to study problem definitions as a form of knowledge representation in engineering. Keywords: generative design; optimisation; computational design; parametric modelling; BIM; automation; shading study 1. Introduction In recent years, technological development has accelerated drastically. This is re- flected in the increasing use of digital tools being introduced in the construction industry. The work of designers over time has already changed by replacing pen and paper with computer-aided design (CAD) tools and now with Building Information Modelling (BIM). Building design is becoming more comprehensive, interconnected, and coordinated, but it still involves a lot of manual work and especially rework. Traditionally, the designer proposes the solution based on their experience, previous projects, and creativity under the given conditions and objectives, while the computers are to help with presentation, documentation, and analysis, but other alternatives may be considered to assist in design development. One such approach is generative design, where the main idea is the collaboration between the designer and the computer/algorithm, which has complementary capabilities, such as, on the one hand, sorting large amounts of data, generating and analysing a large number of results, finding optimal solutions, and iterative improvement of the solution [1,2]; on the other hand, real world experience, deep knowledge, understanding, and history of working in the field. In this process, we shift the focus from creating the design solution to defining the design problem with its constraints and criteria, where a well-defined problem Buildings 2022, 12, 2194. https://doi.org/10.3390/buildings12122194 https://www.mdpi.com/journal/buildings