Relationship Between IAQ And Indoor Temperatures Of Different Dwellings In A Temperate Climate During A Pandemic Summer

This paper investigates the relationship between indoor air quality (IAQ) and overheating in a temperate climate in Spain (Cfb attending to Koppen-Ggeiger classification), in dwellings located in residential buildings and without cooling systems. Twelve dwellings were selected among different Spanish building regulatory periods and quality of construction (before the first regulatory period, 1979; between 1980-2006; and after 2006 with the Spanish Building Code following the European Directive, and with the Passivhaus standard), and located in an intermediate floor and a top floor of residential buildings. Two spaces of each dwelling (living room and main bedroom) were monitored during three months from June to September 2021 (temperature, relative humidity and CO2 concentration). Analysis of monitored data shows dwellings´ performance during all summer where a heatwave took place and during the COVID pandemic, where ventilation was strongly recommended to the population to minimize infection risk at home. Results show a better IAQ in the newer dwellings built after 2006 (with vents or heat recovery ventilation systems) although less overheating was not observed in relation to the older ones, but with significant differences during the registered heatwave, and the relationship between IAQ and temperatures. More efforts are needed to improve the design of new and rehabilitated buildings for an optimal thermal and IAQ performance of dwellings, attending to warming conditions related to Climate Change.