On Thursday, July 23, starting at 4.00 p.m., the doctoral thesis defense of the PhD candidate Annette Naomi Anneli Davis will take place in the Sala de Graus of La Salle Campus Barcelona. The thesis, entitled 'Circular industrialised housing: an interdisciplinary, process-driven framework for climate and housing challenges', has been carried out under the direction of Dr Núria Martí Audí, Dr Ignacio Enrique Guillén Guillamón and Dr Alexandra Cláudia Raebelo Paio. The PhD student is part of the HER research group.
The court is made up of the president, Dr Gerardo Fabián Wadel Raina; the secretary, Dr Michelle Imperia Sánchez Brajkovic; and the member, Dr Xavier Martín Tost.
Thesis summary
This thesis investigates the opportunities and challenges impacting the adoption of Circular Industrialised Housing to address the on-going twin climate and housing crises. This work centres on integrating Industrialised Construction with Circular Economy principles to deliver affordable, environmentally sustainable housing at scale, unlocking the reuse potential of building materials in the future. The aim of the research is to provide professionals involved in the delivery of housing the tools to navigate the complex path towards net zero, limiting the environmental impacts of housing construction and demolition in line with the Paris Agreement, while passing on long-term cost-saving opportunities to residents.
This doctoral thesis is structured as a compendium of four research articles published in peer reviewed journals. Each article addresses a distinct aspect of the overarching research aim and together they form a cohesive narrative that advances the field. Each article contributes to the development of a practitioner-ready framework, which is the main research output.
A Cradle-to-Grave Life Cycle Assessment of a highly energy efficient house in Spain was used to apply circular design theory and current EU guidelines, exemplifying the impacts these assumptions have on the replacement of building parts over a 100-year period. This study, together with Chapter 5, provided the basis of the framework with four key processes rooted in a Cradle-to-Cradle and industrialised approach to the housing lifecycle within this thesis. These are (re)defining, (re)designing, (re)manufacturing, and (dis)assembly, each of which may (re)occur or loop in various orders throughout the building lifecycle; therefore encompassing both new build and existing housing stock.
The framework is grounded by a review paper investigating the state-of-the-art in Circular Industrialised Housing, identifying gaps in the existing literature and establishing application to improving both housing affordability and sustainability. This highlighted a lack of interdisciplinary and practice-based research in the field and the pertinent need for a common big-picture framework into the system-wide factors impacting a circular, industrialised, and lifecycle thinking approach to housing. Within this thesis document, I delve deeper into defining ‘Circular Industrialised Housing’, which is understood through the integration of the terms ‘Housing’, ‘Industrialised Construction’, ‘Design for Disassembly’, and the ‘Circular Economy’.
Alongside these processes, the framework defines six critical overarching factors, 15 themes, and 45 sub-themes impacting industrialised housing during the building lifecycle. These were developed through three iterative studies. The first study completed the framework outline, defining six broad common factors: cultural, governance, financial, site and logistics, construction system and building information. This was achieved with a systematic search and review of academic literature for industrialised (permanent) housing designed for disassembly. Content analysis yielded numerous common themes and sub-themes and identified critical gaps within the defined processes and factors. Two further studies based on interviews and on-site observations provided applied practical data and additional emergent themes and sub-themes. These insights were gained from the Solar Decathlon Europe competition in 2022 and interviews with industry practitioners and factory visits in the Netherlands, the United Kingdom, Spain and Portugal.
All emergent themes and sub-themes were collated and refined to provide a robust framework relevant to industry stakeholders across Europe such as designers, contractors, and housing providers as well as local-level policymakers. As a final step, industry practitioners provided feedback for the proposed outline framework, informing future development whilst further validating its relevance and usability in practice today. The framework and the thesis itself are tools for professionals to utilise in their own work in the delivery of affordable and sustainable housing.