The Hearing Architecture podcast, proudly sponsored by Brickworks, presents Again and Again and Again, a mini-series hosted by Hilary Duff. Each week we bring you interviews and conversations as we seek better ways to understand, harness and deploy the expertise and knowledge of professionals currently within the design community, at home and abroad. Our guests are all experts on circularity within the building industry and share the aim to display that waste is not an accident, but the consequence of decisions made at the design stage. Here is our opportunity. We as designers have an opportunity to do better. In this episode I speak with Maarten Gielen. Martin is an award-winning, Brussels based designer, researcher, professor, and leading practitioner changing the way materials are used in architecture, construction, and engineering. His curated exhibitions, including the 2010 Belgian pavilion of the Venice biennale, the groundbreaking 'Progress' with Rem Koolhaus (2011) and 'Behind the Green Door' for the Oslo Architecture Triennale (2013), underscore his ability to provoke critical dialogue and inspire change within the industry. Maarten, along with Tristan Boniver and Lionel Devlieger, co-founded Rotor in 2006—a collaborative design practice with a specific focus on material flows. Originally conceived as a private yet 'activist' studio aimed at influencing policy and driving change in Brussels' material economy, Rotor has since expanded its impact through various publications, exhibitions, and lectures, contributing significantly to the broader industry. In 2014, Maarten co-initiated commercial spin-off: Rotor Deconstruction, which dismantles, salvages, and sells reused building materials. Here he acted as director, growing the company to around 25 employees, until late 2023 when he shifted his focus to new projects and processes.  His latest initiative, 'Halfwerk,' explores the potential for reusing sheet metal and other materials, challenging traditional notions of waste and promoting local value chains. Maarten's expertise extends far beyond mere practical considerations. He approaches architectural sustainability from a holistic perspective, examining entire systems and supply chains to understand the broader implications of construction materials. He asks us to consider construction material as an object, with the same rigor in which we should consider the void in the landscape from which materials are extracted. To consider the transportation, the storing, the fixing, and the materials at the end of its first considered life. He suggests that construction materials are cultural products whose value extends far beyond the technical.  At the heart of Maarten's work lies a deep interest in reimagining the organization of the built environment. His concern regarding the tremendous quantity of materials we barely use and quickly waste has led to his determination to challenge the status quo and adapt the conventional business model to facilitate material salvage, waste reduction, and the establishment of a circular economy.  Through our conversation, we explore pressing questions surrounding the infrastructure and actions needed to prioritize reuse as a viable alternative to virgin materials and we query what kind of industry we need to build to allow architects to specify second hand materials with the same ease as new materials. This has been Again&Again&Again, a mini-series of Hearing Architecture, proudly sponsored by Brickworks, made possible with the support of the Alastair Swayn Foundation This episode was recorded during a period of residency with the SIM Icelandic Arts Association in Reykjavik. Thank you so much for listening and thank you to our international guest Maarten Gielen of Halfwerk. Thank you for sharing your proposals relating to the new economic models in the material flow register of the building sector and to helping us consider the city as resource. Let’s watch this space and we look forward to