Evaluation of the performance of a building envelope constructed with phase-change materials in relation to orientation in different climatic regions

Minimizing the effect of climatic conditions and energy consumption in buildings are important issues to be considered in the building design process. Due to the changes in climatic conditions, there is an increase not only in the consumption of heating energy but also cooling energy. Certain passive measures to be taken primarily for the building envelope are necessary in order to reduce energy consumption. Applying a phase-change material on the surface of a building envelope is one of the new approaches for controlling heat transfer through the building envelope during the cooling period. It is known that phase-change materials, which are also considered as modern versions of thermal mass concept, can reduce the of a building's heating and cooling energy consumption. In this study, a unit with 10m to 10m dimension with one external facade in a 3 storey building was evaluated in two cities, Istanbul and Diyarbakır, in temperate-humid and hot dry climatic regions. In order to reduce heating and cooling loads, a phase-change material was applied on the surface of the building envelope. The thickness of the phase-change material on the applied surface was increased at every step, and different building envelope alternatives were created. Heating and cooling energy consumptions were calculated for different orientations of the external facade. When calculated values are evaluated comparatively, it is seen that as the thickness of the phase-change material increases, the energy loads occurred in the unit decrease gradually. Equally, the performance of the phase-change materials varies depending on the orientation. Therefore, it is possible to determine the optimum thickness and orientation combination of the phase-change material application on a building envelope and reduce heating and cooling energy consumptions.