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In light of the Paris Agreement's objectives and the related European and Swiss goals of decarbonising the built environment, the importance, relevance, and potential benefits of integrating Building-Integrated Photovoltaic (BIPV) within building renovation processes are acknowledged. Functioning both as envelope material and on-site electricity generator, BIPV can simultaneously reduce the use of fossil fuels and greenhouse gas emissions. Motivated by the current barriers and misconceptions that withhold a widespread integration of BIPV, particularly regarding financial implications and solar exposure levels that are believed to be unfavourable, this paper aims at bringing new knowledge and a rigorous and adaptable method to inform decision-making and promote the use of BIPV in urban renewal processes. Focusing on the architectural design, we here present a methodology to select active (BIPV) surfaces during the retrofitting process based on a trade-off between the self-consumption (SC) and self-sufficiency (SS) of a building. The approach consists in iteratively identifying surfaces that achieve a varying annual irradiation value (threshold). It also includes the evaluation of the effect of electricity storage systems. The methodology and the results of its application are presented through the comparison of two case studies in Neuchâtel (Switzerland). The outcomes of this new approach for addressing building renovation projects in the urban context can help architects, designers and engineers to better size the installation and the repartition of active surfaces in the renovated thermal envelope. Results show that it is important to take into account a larger range of irradiation levels to choose the active surfaces, especially in high-rise buildings with a greater proportion of façade than roof. In such cases, the irradiation threshold can vary between 600 and 800 kWh/m 2 •year depending on the strategy adopted in terms of Heating, Ventilation and Airconditioning

Life-cycle assessment of the built environment tends to focus mostly on operational final energy consumption of buildings located within a specific context. Such limited scope prevents a broader usability of findings in practice. In Switzerland, the "2,000-Watt society" vision provides a theoretical framework towards energy transition. Intermediate targets for 2050 relate to an extensive assessment incorporating environmental impacts of construction materials and use of a building, and of induced mobility of its occupants. Accordingly, it becomes crucial to gather information about the current building stock performance and its transition potential. The paper aims at contributing to the sustainability transition debate by providing a comparative assessment of retrofitted and new residential buildings representative of the Swiss building stock. A direct output could constitute in establishing a reliable reference dataset to support practitioners' or lawmakers' future decisions. The novelty of the study relies on two aspects: 1-on adopting an interdisciplinary approach to propose an overview of the current status and transition potential of the built environment; 2-on building a methodology able to extrapolate results for large-scale studies of neighbourhoods or larger built areas. Based on the definition of four building archetypes, this study assesses four scenarios decomposed into four to six variants. The scenarios consist in varying the building energy-performance, while the variants implement different locationsamong urban, peripheral and rural areasand different passive or active strategies. Results are expressed in terms of non-renewable primary energy consumption and global warming potential. They highlight in particular the performances of renovation projects, the effect of high-energy performance on embodied impacts, the low-level of performance of single-family houses and the significant impact of mobility related impacts.

As tomorrow's cities are already largely built, many strategies stress the importance of urban renewal processes to address current energy issues. This paper focuses on the Spanish residential building stock built until 2001, which has a low level of energy performance.Considering the current economic crisis, the future lies in renovating the built environment, which holds a significant energy-saving potential. This potential is here quantified by applying the cost-optimal methodology, initially proposed by the Energy Performance of Buildings Directive, and which calculates costoptimal levels of minimum energy performance requirements at the building and component scale.The originality of our study lies in the application of this methodology at the territorial scale, comparing different retrofitting scenarios by scaling-up building-scale results through an archetypal approach. We also describe an Excel-based tool allowing two types of studies: (i) at the building scale, for one archetype in a particular climatic zone; (ii) at the territorial scale, to have an overview of all building archetypes and climatic zones simultaneously. Results include economic aspects, energy consumption and savings and associated emissions.The outcome can help construction-sector firms adapt their business plan, while also providing stakeholders with decision-support to promote a sustainable renewal of the building stock.

The regeneration of urban brownfields is a relevant strategy to limit the sprawling of post-industrial European cities. However, the integration of sustainability issues in urban brownfield regeneration projects is not a spontaneous process, remaining in most cases partial or superficial. Achieving the goals of sustainable development requires high global quality objectives, integrated into the project dynamics, and a continuous monitoring of environmental, social, and economic indicators, adapted to the specificities of brownfields. Following these considerations, an operational monitoring tool facilitating the transformation of urban brownfields into sustainable neighborhoods was created. This paper presents and discusses the verification stage of the tool, divided into two complementary tests: 1) test-applications on three case studies in Belgium, France and Switzerland and 2) interactions with the involved stakeholders. First, we describe the functioning of the tool. Then, we present the test-applications results, focusing on the Val Benoit project in Liège (Belgium). They are followed by the interactions with the stakeholders that took the form of roundtable discussions. Finally, we discuss the performance of the tool looking at its potential added-value. It reveals that an adapted operational monitoring tool can facilitate sustainability assessment, reporting, decisionmaking and multidisciplinary collaboration. Globally speaking, the integration of monitoring practices appears not only feasible, but also realistic and desired.

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