Retrofitting buildings across entire city districts with modern insulation, heating systems and other new construction techniques is a cost-effective way to improve energy efficiency. But the variety of urban areas in Europe means there is no one-size-fits-all solution. EU-funded researchers have developed a macro-level modelling tool for sustainable district retrofitting that takes into account Europe's broad urban diversity.
From ancient city centres built up in the Middle Ages to decades-old high-rise apartment complexes, all types of urban area stand to benefit from solutions developed in the FASUDIR project to help decision-makers select optimal sustainable retrofitting strategies.
The main outcome of the three-year initiative is an integrated decision support tool and connected repository of energy efficiency technologies. These allow urban retrofitting projects to be modelled in a 3D environment with different heating, insulation and other energy efficiency solutions tested virtually.
“The decision support tool enables retrofitting projects to be designed from the ground up, taking into account the input of different stakeholders such as local residents, investors and public officials,” explains Giulia Barbano, the FASUDIR project dissemination manager at iiSBE Italia R&D. It also means the technologies and materials used in the retrofitting are “optimally suited to the local climate, type of construction and societal and economic factors”.
The web-based tool allows retrofitting project managers to select technologies and systems that can be applied at building and district scale, offering information on expected energy performance as well as cost considerations, potential social impacts, energy synergies and user comfort. By testing different solutions virtually, decision-makers can easily and quickly optimise retrofitting strategies and take better advantage of economies of scale, while energy efficiency innovations gain greater visibility through inclusion in the repository.
Used widely, the FASUDIR system could make a significant contribution to improving the energy efficiency and cost-effectiveness of urban areas across Europe, helping to meet the EU’s target of cutting energy consumption by 20 % by 2020. It would also generate economic benefits for the construction sector and improve quality of life for urban residents.
Crucially, the approach enables all stakeholders to provide feedback on projects before work begins, allowing decision-makers to address concerns and adapt retrofitting sustainable strategies to the local context. Such stakeholder feedback loops have been at the heart of the innovative design of the FASUDIR system from the outset.
“Key actors have been involved from the start in the … support tool development through the establishment of local project committees, including experts on urban planning and retrofitting in all project countries. The committees have convened at key moments, first at the beginning of the project as part of a consultation on the current needs and key issues in district-scale retrofitting, then for an expert review of the developed methodology,” Barbano says.
To validate the approach, the FASUDIR team conducted three case studies in diverse urban areas in Europe: a prefabricated housing estate in Budapest, a residential development in Frankfurt built in the 1970s, and part of the historic city centre of Santiago de Compostela, a UNESCO World Heritage site. Models developed in the case studies form the basis for retrofitting projects in those areas, while commercial versions of the tool are set to be developed by the project partners for wider application.
“The three pilot areas are very different in terms of building ownership, population profile, climate and retrofitting needs,” Barbano says. “The fact that the FASUDIR tool offered effective and sustainable solutions in each case reflects the high potential of the system to address the retrofitting needs of a variety of urban areas.”