Climate-Robust Roof Typology Selection for Covered Courtyards in Heritage Buildings: A Comparative Case Study Under Present and Future Climate Scenarios

Covering courtyards is a strategy for adapting heritage buildings to new uses, but its environmental effectiveness depends on the overall roof configuration and may be compromised by future warming. This study evaluates three translucent roof typologies—a sawtooth roof with south-facing vertical glazing (SAW), a semi-dome (SD), and a flat glazed roof (FLAT)—for a historic courtyard in Burgos, Spain. Performance was assessed through incident solar radiation, free-running indoor thermal behaviour, and annual heating and sensible cooling demands. The analysis comprised 27 simulations combining the three typologies with the current climate and four Shared Socioeconomic Pathways for 2050 and 2080. All eight future weather files were generated by morphing a single baseline TMY using ensemble-mean climate-change signals; consequently, inter-model dispersion and alternative downscaling or weather-generation methods were not assessed. Warming consistently reduced heating demand and increased sensible cooling demand, although the annual response differed among typologies. SAW achieved the lowest combined demand under all conditions, decreasing from 204.41 kWh/m2·year under the current climate to 153.53 kWh/m2·year under SSP5-8.5 in 2080. Over the same range, combined demand decreased from 261.37 to 235.49 kWh/m2·year for SD but increased from 224.61 to 238.02 kWh/m2·year for FLAT, as rising cooling requirements outweighed heating reductions. These results demonstrate that the combined effects of roof form, glazing orientation, glazed-to-opaque distribution, and resulting solar exposure govern thermal performance and sensitivity to future warming. Within the analysed decision set and weather-generation framework, SAW achieved the lowest combined thermal demand under all nine climatic conditions and was therefore identified as the minimax-regret alternative. This preference is limited to the thermal-energy criteria evaluated; conservation compatibility, reversibility, structural feasibility, fire safety, watertightness, maintenance, and visual compatibility with heritage values were outside the scope of the study. These findings are specific to the modelled building and should not be extrapolated to other courtyard geometries, orientations, construction systems, or climatic contexts without further case-specific analysis.