Much of the social housing stock in southern Europe is obsolete in energy terms, with users who also present very specific socio-economic profiles requiring in-depth study. Proposals for this type of housing stock of current energy retrofitting policies, based on standardized user patterns, will only contribute to increasing the 'performance gap' between real and estimated consumption. This study evaluates the thermal comfort conditions and energy consumption in the specific case of social housing in southern Spain, under a severe summer climate. This evaluation is based on in-situ data measurements of three housing units in use. This paper aims to test which adaptive comfort models work best in the specific conditions of the case studies and to identify the user behaviours which reduce thermal comfort. Thus, real user patterns were established and measured data were analysed. The results show that the case studies are in discomfort conditions during a high percentage of occupied hours, mainly due to the severe climate and the unsuitable use of passive measures including natural night-time ventilation and solar protection. This situation worsens with limited use of local cooling systems due to financial constraints. National regulations should define different retrofitting targets based on climatic and socio-economic conditions.