Multi-criteria assessment framework for sustainable rehabilitation and reconstruction of housing using mathematical model

Although there has been considerable interest in innovative architectural and technical solutions for energy rehabilitation of housing, there has been less focus on environmental rehabilitation, which requires more rigorous processes and approaches to minimise environmental impact. This paper addresses this gap by evaluating the environmental performances of traditional Saharan single-family houses and contemporary European multi-family dwellings, in arid and oceanic-continental climates. The assessment was conducted using a multi-criteria indicator system based on a mathematical model and combining four impact categories (cumulative energy demand, resource depletion, greenhouse effect and smog), five indices (thermal, energy, environmental, morphological and metabolic) and four scenarios. The study indicates that the use of low-energy heating and air-conditioning (HVAC) systems and appropriate thermal zoning with insulated walls can reduce the heating demand of dwellings in oceanic-continental climates by 33.5% and 12% respectively. Additionally, the use of stone in the same climate can reduce the initial requirements of the baseline variant by up to 36.5%. The strategies employed ensured environmental optimization, along with a closed island morphology featuring offsets ranging from 0 to 45% from the reference. In arid climates, standard masonry optimized the energy performance of Saharan dwellings, reducing their heating needs by 31% and their cooling needs by 35%. This strategy, along with the patio and a closed island morphology, optimised their environmental performance, with reference offsets ranging from 0 to 41%. A tool has been developed to promote sustainable development in the built environment by enhancing codes and regulations for sustainable construction and rehabilitation operations.