Envelope insulation and heat balance in commercial buildings

This paper presents a methodology to evaluate the influence of different components of the annual heating and cooling load of buildings, analyzing the energy performance of building surfaces that are exposed to different weather conditions. The analysis was carried through the heat balance method by using the EnergyPlus program and weather files for Denver, in the United States and Florianopolis, in Brazil. The third floor of a building of 5-floors office building was used to analyze different optimum insulation thickness on external walls based on annual heating and cooling loads. The study reveals the possibility to analyze the heat gain and loss through the opaque elements. For Denver, the increase in the heat transfer coefficient resulted in an increase of the model total thermal load. However, for Florianopolis the increase in the wall’s heat transfer coefficient provided a reduction of 14% in the thermal load value. In addition, analyzing the walls with a low value of absorptance resulted in a lower value of total thermal load.