STRATOCONCEPTION ® , AN ADDITIVE MANUFACTURING PROCESS FOR TIMBER ARCHITECTURE: CHALLENGES AND OPPORTUNITIES Victor Fréchard 1 , Laurent Bléron 2 , Julien Meyer 3 , Franck Besançon 4 , Gilles Duchanois 5 ABSTRACT: The additive manufacturing has been recently adopted by the construction industry to overcome the existing design limitations and to build large-scale structures. The timber architecture and construction have not yet adopted the additive manufacturing technologies. This paper focuses on the understanding of the use of the Stratoconception ® additive manufacturing process for timber architecture and construction by identifying the opportunities it offers and the challenges it presents. First, we outline the Stratoconception ® process. Furthermore, we highlight and assess by experiment the opportunities and the challenges of the implementation of this process. We target the complex shape design and the multi-functionalization of the components as important opportunities that can lead the design of new high-value building components for timber architecture. Next, we introduce the potential use cases for the process and emphasize the capacity of the technology to be implemented in the common timber construction practices. The lack for Stratoconception ® use in the context and in the dimensions of architecture brings the challenges of scaling- up the process and integrating it into the multicriteria architectural design process which exceed the existing methods and tools. We describe the overriding issue of managing the waste of material caused by the micro-milling phase of the process. The building of a knowledge base of relation between Stratoconception ® and timber architecture reveals the need for an adapted and efficient design framework for the process use for timber architecture projects. Thus, we propose and describe a theoretical design framework achieving the integration of the AEC issues into a design process and fostering the development of new efficient building components by guiding the designer towards rational decision making. KEYWORDS: Timber Architecture, Additive Manufacturing, Stratoconception ® , Design for Additive Manufacturing, Computational design 1 INTRODUCTION 678 1.1 CONTEXT The adoption of computational design and digital fabrication in architecture, based on Computer Numerical Control (CNC) machining and robotics, fosters a development of an innovative, efficient, and expressive contemporary timber architecture [1]. The formal and structural advances from the digital tools adoption encompass an emergence of new architectural tectonics [2-4], which in the current environmental context are fostering the use of timber [5]. The Additive Manufacturing (AM), comprising a range of processes [6,7], shares the common origin with CNC machining but differs in the ability to produce directly the high level of complexity parts that cannot be achieved by subtractive or formative methodologies. In recent years, we have observed a substantial increase in research topics studying the use of AM methods and their first implementations in the construction industry [8-11] for the large-scale building components and structures by applying the processes based on cementitious materials 1 Victor Fréchard, LERMAB, Nancy National School of Architecture, France, victor.frechard@nancy.archi.fr 2 Laurent Bléron, LERMAB, University of Lorraine, France, laurent.bleron@univ-lorraine.fr 3 Julien Meyer, MAP-CRAI, Nancy National School of Architecture, France, j.meyer@nancy.archi.fr [12-15], alongside with earth-based [16,17], sand-based [18], polymeric [19], or metal materials [20]. The motivations for the adoption of AM by the construction industry mainly focus on the productivity gains, the reduction of materials waste, the worker availability and safety, or the reduction of the production cost of the complex parts. Also, these motivations correspond to the core challenges of the automation in construction and of digital fabrication adoption. The AM use today is often limited to these core challenges but does not “reshape the way we think about architectural components”[21]. According to Labonnote et al. [8], an architectural paradigm shift exploring the inherent potentials of AM is required to improve current construction design approaches. To foster this paradigm shift, the AM constraints must be considered on the early stage of the design, to allow rational decision-making. Furthermore, the environmental issues require for the use of more sustainable, renewable, and non-petroleum-based materials. Wood could be used in several AM processes [22-24], however the research and technology advances are still needed to meet the requirements of large-scale construction. 4 Frank Besançon, MAP-CRAI, Nancy National School of Architecture, France, franck.besancon@nancy.archi.fr 5 Gilles Duchanois, MAP-CRAI, Nancy National School of Architecture, France, gilles.duchanois@nancy.archi.fr 3708 https://doi.org/10.52202/069179-0482