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• A study on housing stock improvement potential in Mediterranean areas is presented. • Three typical case studies were chosen from the stock of a southern Spanish city. • Monitoring on environmental and electricity data and tests logged real performance. • Energy models were built and adjusted based on real occupancy conditions. • The considered building retrofits raise indoor temperature and reduce discomfort. Renovating buildings is one of the major targets within the current European goals toward decarbonized cities in 2050. The residential stock offers extensive opportunities to achieve current energy horizons, since more than 75% of the existing buildings in the European Union are energy deficient, with poorly insulated thermal envelopes which drive indoor conditions far from current comfort standards. This paper aims to provide a protocol for forecasting the upgrading potential of this housing stock in southern Europe, particularly in Mediterranean areas, identifying the level of obsolescence and possibilities for improvement, especially in winter indoor thermal conditions, offered by standard passive strategies. Following an architectural, constructive, and energy analysis of common patterns throughout the urban stock of the southern Spanish city of Córdoba, three case studies built-in 1951–1980 – pre-dating the first Spanish regulations on thermal conditioning in buildings – were selected for the assessment. Long-term monitoring and in situ tests (i.e., infrared thermography, airtightness) recorded the performance of these buildings under real occupancy conditions, subsequently incorporating them into the calibration of simulation energy models, aiming to predict the potential improvements after implementing standard passive strategies in these buildings. Results show that building retrofits not only improve the quality of indoor thermal conditions by increasing indoor temperatures by 3–4 °C but also almost eliminate occupied hours outside the comfort range. [ABSTRACT FROM AUTHOR]

Temperatures in Mediterranean cities are rising due to the effects of climate change, with a consequent increase in the heat waves frequency. Recent research has shown the tempering potential of semi-outdoor spaces such as courtyards, which are semi-enclosed spaces that are widely used by the users of buildings in Mediterranean cities. International standards addressing thermal comfort parameters provide technical guidelines for indoor spaces only. Expanding this concept, this paper focuses on the potential to extend and interpret the existing calculation models for indoor thermal comfort, EN 16798 and ASHRAE 55, to determine thermal comfort, monitoring two different courtyards in Cordoba, Spain, during both typical summer and heat wave periods. The results show that during the typical summer, the monitored courtyards can reach temperatures up to 8.4 °C cooler than outside. Subsequently can be considered to be in thermal comfort on average for 88% of the time according to EN 16798, and 75% according to ASHRAE 55, which drop to 71% and 52% respectively during heat wave (HW) periods, in spite of increasing thermal gap (TG) up to 13.9 °C. The results are also compared with the PET indicator used for evaluation of outdoor thermal comfort, which provides comparable figures: 81% summer and 73% HW. Implications of implementing passive shading strategies to increase comfort in these transition spaces are also evaluated. The research highlights the thermal potential and usefulness of courtyards in warm climates, so they can ultimately be included in the building analysis as a potentially comfortable and habitable space. • Courtyard was included in the building analysis as a comfortable and habitable space. • Comfort adaptive assessment according to EN 16798, ASHRAE 55 and PET were confronted. • Courtyard tempering achieves a TG up to 8.4 °C in summer and 13.9 °C in a heatwave. • In warm locations, courtyards can be under comfort more than 75% of the day. • Shadow quantification proves to be a major strategy regarding extreme temperatures. [ABSTRACT FROM AUTHOR]