Evaluation of comfort and thermal efficiency in buildings with plant surroundings: An experimental study report

Abstract

With the advancement of science, mankind is increasingly understanding the relationship of climate and weather with geographic space. This provides a holistic view that enables the development of techniques that help minimize the impacts of these climatic variables on our daily lives. The present study aimed to analyze the thermal comfort of four “test cells”, representing the basic standard Brazilian construction model, in view of the local climate. Each installation was subjected to different combinations of green facades and roofs and underwent temperature measurements over the course of one year. The adaptive comfort index suggested by ASHRAE was used, which establishes a methodology to determine the degrees-hours of discomfort perceived by users within a structure. The test cells with green facades and the cell with green facades and a green roof exhibited a decrease in periods of discomfort. Regarding discomfort due to cold, the green cells presented higher temperatures than the test cell without plant surroundings; when such discomfort was due to heat, they exhibited lower temperatures in most hours. These findings highlight the potential of this technique in reducing the operational costs of buildings to maintain thermal comfort. After calculating the number of cooling hours needed to obtain comfort, the test cell with green facades and a green roof required 212h (equivalent to a consumption of R$181.10), while the control cell, 455h (equivalent to a consumption of R$388.60), thus demonstrating the efficiency of using plant surroundings in buildings, which increase thermal comfort and reduce costs with air conditioning.