Thermal Performance Assessment of Vernacular Earth Buildings in Tropical Climates: A Case Study in Costa Rica

Abstract

Thermal mass is a common concept applied in vernacular architecture to keep internal temperatures comfortable by damping and delaying heat transfer through the building envelope. However, despite the widespread presence of large mass buildings in tropical regions, it has been argued in the literature that thermal mass is not efficient in tropical climates due to the minimal difference between night and daytime air temperatures. This study aimed at evaluating the thermal performance of heavyweight buildings to determine whether the use of thermal mass is effective in maintaining internal temperatures within acceptable limits. Six adobe and bahareque buildings with large mass earthen walls were monitored in two tropical climate zones recording internal and external temperatures in both rainy and dry seasons. Three performance indicators were used: general temperature damping, peak temperature reduction, and the proportion of time within 80% thermal acceptability limits. The results showed that the buildings were able to dampen peak high and low temperatures by an average of 5 ∘C (2.7–9.7 ∘C), reducing peak outdoor temperatures by up to 5 ∘C, and increasing the time within thermally acceptable limits. This chapter demonstrates the viability of using thermal mass in tropical buildings as a technique for mitigating global climate change.