SBE25 Trondheim, Cities and Climate Change – 24-27 November 2025, Trondheim, Norway
The Urban Retrofit team travelled to Trondheim in late November for a conference hosted by NTNU University – the Norwegian University of Science and Technology. Although the sun rose late and the pavements were icy and hazardous, the winter lights illuminating the windows of offices, restaurants and people’s homes lent the city a warm and inviting quality.
Part of a long-standing series, the SBE (Sustainable Built Environment) conference brings together an international and interdisciplinary mix of participants researching sustainable construction and urban development, with a predominant focus on sustainable building technologies, architecture, engineering and environmental assessment. The starting point of the conference was stark: the built environment is responsible for over 40% of global greenhouse gas emissions and primary resource consumption – hence the conference theme: ‘transforming cities towards climate neutrality and circularity’.
We came to Trondheim with two objectives: first, to learn about emergent scholarship in academic fields that are highly relevant to urban retrofit but not always aligned with planning and social science scholarship, notably on life cycle assessment (LCA) and other quantitative tools for measuring the carbon output of buildings. Second, to gauge how these wider disciplines might react to the planning and development systems focus of urban retrofit and our intended use of qualitative research tools to examine case studies that extend beyond the building level.
The quest for measurement
As a team, we have become increasingly conscious about the need to measure how urban retrofit interventions contribute to meeting the net zero goals set out by policymakers. Engaging in an event where the vast majority of participants were from the scientific community and had extensive experience measuring the built environment’s carbon output felt important and was to prove extremely informative. We heard numerous presentations detailing ways of measuring the carbon output of different typologies and materials, and assessing the success of creating and maintaining nature-based solutions within the public realm. We even learnt about how the climate agenda is impacting national defence decision making on facilities and logistics in Nordic countries.
Absorbing so much that was new and unfamiliar led to us make two critical observations. First, the overall thrust of the conference was very building-focused (a limitation acknowledged by the presenters themselves). Rarely did the studies interrogate human behaviour. This left us wondering, for example, whether people use the energy systems in their homes effectively or if the inter-relationship between buildings and neighbourhoods had been fully considered. Second, we found ourselves thinking, “what next?” While impressed by the data generated, we nevertheless questioned how this data can be harnessed and used to shape governance and planning decision-making that effect system-level change in cities.
Sufficiency: a provocation
Two particularly fascinating presentations by Loli Arian and Lina Eriksson explored the concept of ‘sufficiency’. Although aware of this emerging concept, the two presentations helped clarify the clear distinction between ‘sufficiency’ and the more widely understood concept of ‘efficiency’. For the presenters, ‘sufficiency’ offered a critical means of exploring how spaces in buildings can be optimised in environmental terms. In short, this presupposes that smaller spaces within residential buildings (i.e. fewer square metres of living space in a home) plus higher occupancy offers a means of creating more environmentally sustainable (i.e. denser) buildings and neighbourhoods.
As planners, we were left thinking about the quality of these diminutive spaces. Smaller spaces may be more environmentally sustainable, but are they socially sustainable? Will those who have the least means end up in smaller living spaces while more affluent people continue to consume more space? Might sufficiency in this context therefore hinder efforts to achieve a just transition? We also wondered whether a policy emphasis on smaller units, without an attendant focus on quality and equality, might simply offer developers an opportunity to build at higher densities and generate greater returns.
The quantitative-qualitative data divide
The level of scientific rigour and data collection on display as SBE25 Trondheim was impressive. There is huge effort being applied to quantification and assessment, which is essential if we are to ‘know’ with any certainty whether progress towards net zero is being made. However, we did speculate as to whether the quest for data could create inaction or even distract from improving governance and decision-making. Perhaps this is a classic social science response and highlights the pervasive quantitative-qualitative divide that we are humbly attempting to bridge. Much more positively, however, is how welcomed we were by the SBE community. Amusingly, perhaps, we were praised for our ‘interesting social science questions’ and encouraged into dialogue about what could be achieved by bridging disciplinary boundaries.
Concluding thoughts
We left Trondheim thinking that continuing interdisciplinary dialogues were vital to ensuring quantitative research on the built environment asks more political questions and qualitative research becomes more confident to engage with technical, data-rich evidence. In that regard, the SBE conference reinforced the importance of measurement as a critical fourth dimension of urban retrofit – something we set out in our recently published evidence review. Critically, however, any such measurement must include quantitative data (e.g. LCA) alongside the more qualitative data of lived experiences of place and the political of governance and delivery. The twinkling winter lights in Trondheim’s windows perhaps offer an apt metaphor: data can illuminate what we need to see, but only if we’re prepared to look – and then to act.
