Hygrothermal performance monitoring and indoor thermal evaluation in adobe structures

Abstract

Adobe masonries are high thermal mass walls, as they have the ability to store thermal energy. The high thermal mass of adobe enables the regulation of indoor thermal environment through time lag. This study aims to investigate the thermal performance of adobe masonry in Cyprus and its impact on the indoor thermal conditions. For this purpose, in-situ long-term monitoring was carried out for two years, covering the indoor and outdoor environmental conditions of a typical large-size room, belonging to a historic earthen structure. Laboratory measurements were also undertaken to estimate the thermophysical properties of the main masonry material (adobes). Thermal inertia and decrement factor were calculated based on the laboratory and in-situ measurements. For the evaluation of the indoor thermal conditions of adobe structures, operative temperature and degree hours outside the higher and lower limit margins were used as performance indicators. Moreover, relative humidity was assessed using the higher and lower limit margins. The analysis highlights the beneficial thermal properties of adobes, showing a high thermal inertia (∼5 h) and a low decrement factor (<0.05) for adobe walls; these contribute to the delay of heat transfer and reduced temperature variations (not higher than 1.1 °C) between the external and internal environments of adobe structures, thus leading to improved thermal conditions, especially during the summer period.