Developing a grading tool for sustainable design of structural systems in buildings

Abstract: Construction is known for consuming large quantities of raw materials and high amounts of energy. In 2018, the construction industry was responsible for 6% of global energy consumption, 11% of global CO2 emissions, and approximately 36% of the total waste in the European Union. These drawbacks are just a part of the gap between the construction sector and Sustainability, which can also be perceived as challenges to the industry and demands for new and innovative strategies to increase Sustainability. For example, recent efforts of EcoDesign on structural systems show a trend in the importance of materials efficiency, durability, adaptability, and reuse.    This thesis aims to create a set of guidelines that will help designers and other construction stakeholders apply Design for Deconstruction and Adaptability DfD/A principles to increase the knowledge of how structural design and structural systems in buildings can be designed to promote Sustainability. For this purpose, a grading tool to assess structural systems based on the ISO 20887 was developed. The general methodology for this research was adapted from Design Research Methodology with a particular focus on the Product Development approach for the tool development. A literature Review was conducted in both scientific and grey literature to identify relevant information and current efforts on sustainable design of structural systems and application of DfD/A principles on the construction sector. Three additional methods for data collection were used: (1) questionnaire for identification of customer needs and expectations, (2) benchmarking to identify similar tools, strategies, and certifications systems that include sustainability performance in buildings; and (3) workshops with the purpose to rate the usefulness quality of the tool based on the application of the tool by potential users in different case studies.  A ready-to-use computer-based EcoDesign tool was developed. The assessment performed by this tool consists of an indicator system of DfD/A strategies to enhance sustainable development by improving material efficiency and stimulate a circular economy in the construction sector. A top-down approach was used for the concept generation, which starts with the ReBuilding Index as an indicator of sustainable performance for structural systems. This index is based on five categories defined on the relationship of the DfD/A principles with the design process of the structural system. A total of 20 principles are distributed in these categories, defined by 54 strategies to reach the goal of the principles.     The tool was tested by 11 potential users with different roles in the construction sector. Five case studies were selected to grade the design of five different typologies of structural systems. The usefulness quality of the tool was evaluated based on indicators of usability, utility, and user experience. It was found that developing the tool based on DfD/A principles and the ISO 20887 gave the tool a solid theoretical background and a flexible structure that can be used for sustainable design or as part of an extensive framework of certification systems or ecolabel programs. The tool accomplishes the goal of grading and helping to improve the structural design. However, during the evaluation of the tool, many barriers and difficulties of application were found. Therefore, these findings and obstacles are instead identified as challenges and turn them into opportunities for improvements in future versions of the tool.