Performance and Economical Analysis of Different Insulating Materials Used to Reduce the Heat Load of an Existing Residential Building

Abstract

The energy consumption from the residential sector is an important element which has an impact on the total energy consumption in any country. The heating and air conditioning loads can be reduced through many means. Using thermal insulation in buildings does not only contribute in reducing the required air conditioning system size, but also in reducing the annual energy cost for the whole building. In this case, the energy saving varies according to the building type, the climatic conditions at which the building is located as well as the type of the insulating material used. In the present study, an existing single family house has been studied by applying two main solutions to insulate the walls and the roof using six different materials on the exterior walls that have the most heat gain, such as silica aerogel, polystyrene foam boards (XPS), spray cork, glass ceramic, cool coating enforced by phase change material (PCM), and straw boards. The study took place in El-Shorouk city, Egypt. The energy analysis was estimated by using TRNSYS simulation for the total internal house loads in summer season (June, July, and August) to be 13410 kW. The prototype house is about 300 m2 on two floors and a roof. The results showed that the aerogel has the best insulation followed by XPS then straw boards and glass ceramic which have efficiencies of 48.33%, 38.36%,36.46% and 34.38%. Because of its economical and environmental aspects, straw boards were selected to apply further investigations to indicate the relative efficiencies for the offered solution with the corresponding cost analysis.