Building sector is responsible for 39% of global carbon emissions, which makes it a main actor for climate change due to its high greenhouse gas emissions. Further, it is estimated that this 39% is total of 11% Embodied Carbon emissions (mainly the carbon emissions during construction processes and material production processes) and 28% Operational Carbon emissions (mainly the carbon emissions during the operation period of the buildings, for e.g., carbon emissions due to heating and cooling systems). Despite of achieving remarkable results in reducing operational carbon, the embodied carbon is increasing proportionally to the total carbon emissions. And, if no steps taken to focus on embodied carbon, then it is estimated that it can increase up to 57% of the carbon emission by building sector, by 2040. For these reasons it is imperative to focus on embodied carbon right from the initial design stages of new, extension, or renovation building projects. The key sources of the carbon emissions during the construction of any building system are the structural elements and building skin elements. That is due to the “Upfront Carbon” emissions by high consumptions of fossil fuel-based carbon intensive materials like cement, steel for main structural elements and aluminum for the façade elements. Thus, to focus on Upfront Carbon from early stages of designing is crucial to mitigate embodied carbon.

Hence, the purpose of the project here is to develop “An envelope” for the extension proposal from the Delft Student Rowing club - Proteus Eretes. To fulfill the purpose and to answer the research questions set in the research framework, the project is divided in to four phases, Research phase, Concept phase, Engineering phase, and Reflection phase.

Research phase includes the set of literature research, case studies, and interviews. It involves the understanding of the requirements of Proteus Eretes for the extension. Most importantly it consists of the understanding of various protective and technical functional requirements such as Insulate, Support, and Protect of the building envelope. To focus on embodied carbon of the building envelope, during research phase, the study of embodied carbon is subdivided in to three parts “Focus – Calculate – Mitigate”. By focus, it means to understand every life cycle stage of the embodied carbon as a part of whole life cycle approach, and then calculate the global potentials of the materials used, by referring to the EPD’s. And then mitigate part includes various mitigation strategies and tools. Here, circular design strategies such as design for disassembly, design for adaptability, and design for reuse are employed with the integration of carbon sequestering materials in the Product Development Methodology, during the Concept phase. Further in the design development the fundamentals of Prefab building process are considered by making the whole design modular and produced using one digital carpentry machine. The Engineering phase consists of the in depth planning of assembly order of the components in factory and on site. Thus, making the final design building envelope constructable with circular design principles and carbon sequestering materials to mitigate its embodied carbon.

Key words – Embodied carbon, Upfront carbon, Extension, Building envelope, EPDs, Circular design, Design for disassembly, Design for adaptability, Design for reuse, Carbon sequestering, Prefab building process, Digital carpentry, Product Development Methodology