Sustainable building renovation for an ageing population: Decision support system through an integral assessment method of architectural interventions

Abstract One of the global challenges of the 21 st century is to guarantee adequate residential conditions for the ageing population, by regenerating obsolete urban environments. In addition to compliance with environmental policies through energy retrofitting, a sustainable urban renovation process involves ensuring optimal conditions in security, habitability, and comfort through residential adaptation to the new requirements. This research develops a new method for the analysis and decision-making process in residential retrofitting. This is an open and flexible methodology that has been applied in three reference case studies in Spain and Portugal. Starting from a technical and social diagnosis, the set of measures is analysed through multiple sustainable issues, structured into four main blocks: Technical Requirements and Peoples demands; Constructive Process; Social benefits; and Economic revaluation. The results show the overall and detailed assessment of each measure, and a cost-benefit ratio, which informs the promoter as to ascertain the benefits and drawbacks of each measure. There are measures that exceed 80% of the maximum benefit and achieve an integral revaluation of the property value, as well as measures that exceed 50% of the benefit with investments of less than 1,000 € per dwelling, thereby achieving significant improvement in their quality of life.