First reliability assessment of the coheating test in a semi-desert climate. Identification of the performance gap regarding the Spanish regulation calculations

Abstract

Coheating test is a widely known method for estimating the heat transfer coefficient of unoccupied buildings. However, it does not exist enough evidence of its application on a broad scope of climatic conditions. This article, presents the analysis of a coheating test carried out in a single-zone building placed in the Tabernas desert (South-East Spain). A test campaign of more than two months, between February and April 2021 was analysed. Coheating test was able to provide consistent results, as all the HTC estimates laid within a 6% from the mean. The effect of solar radiation, ground losses and wind speed was also studied.Along with the coheating test, a theoretical estimate of the HTC was calculated. It was based on the method proposed by the Spanish regulation framework for buildings (CTE). Air infiltration measurements were also used to improve the theoretical estimate. Finally, the theoretical and the experimental values were compared. A performance gap between 23% and 40% was found.