Thermal performance evaluation of traditional walls and roof used in tropical climate using guarded hot box

Abstract

Buildings provide appropriate thermal comfort for the people residing in it. Buildings provide this thermal comfort via interaction with the external ambient through walls, roof and glazing. As a result, a prior knowledge of the thermal performance of walls, roof and glazing can help estimate the heating or cooling loads on proposed HVAC systems. The purpose of this study is to investigate the thermal performance of walls and roofs commonly used in residential building sector in India. This is done by determination of overall heat transfer coefficient or U-value using guarded hot box test facility. Detailed description into the calibration procedure of the test setup prior to the actual testing has been discussed at first. The overall testing procedure is in accordance with BS EN ISO 8990:1996. Thereafter effect of varying differential air temperature on overall heat transfer coefficient of reinforced cement concrete roof and three types of burnt clay brick wall configurations are studied. From the regression analysis, one can easily evaluate the U-value of the walls and roof for any differential temperature as experienced by buildings in various climatic zones in India.