Enhancing building envelope performance and resistance in the high mountains of Lebanon

Abstract

In the high mountains of Lebanon, internal comfort heavily relies on fuel consumption for indoor space heating. Being a country that lacks natural resources such as fuel and gas, the energy sector in Lebanon had been unable to meet the market demand for a long time. The simple solution that was adopted to compensate for the electricity shortage over the past years was to rely on private generators for power supply. This solution urged additional energy costs for heating and cooling demands through the inefficient use of air cooling and heating, and since cooling and heating depend primarily on fuel. Studies around the world have shown that 40% of the global energy used in the residential sector is mainly consumed by heating and cooling systems (Aznabaev, A. et al., 2016). As for Lebanon, several studies had been conducted by local and international experts to investigate this issue. These studies recommended specific thermal property for each building envelope in each climate zone in Lebanon to reduce energy demand for heating and cooling. Thus, these recommendations had not been taken into consideration, where we can notice the same building materials used everywhere regardless of the difference of climate characteristics from region to the other. Moreover, the Lebanese building code does not take into consideration the specification of building materials according to climate nor imposes any material restrictions except intermittently the definition of the required percentage of exterior finishing of stone cladding and roof tiles in certain land zones. Therefore, we see the essential need to define the types of construction materials according to each climatic zone. The built environment in Lebanon is mainly composed of masonry systems and concrete products as primary construction materials. This critical observation, where the frequent use of the same construction materials in all types of climates, raises the question on how to use high thermal construction materials in an extreme environment of Lebanon to decrease energy demand for heating and cooling. To reach this goal, the study investigates the thermal performance of residential buildings of various construction types. It takes as a case study the town of Bcharre, located in the high mountains of North Lebanon. The method used in this study compare different types of envelope materials such as concrete masonry unit, reinforced concrete, natural stone, and wood. Besides, an economic analysis is done. In order to find the construction material with the highest thermal properties that reduce energy demand and consumption, this thesis analyzes the energy report of each material and compare it through Insight 360 software. Besides, this comparison will help to understand the behavior of building envelope materials in the high mountain of Lebanon climatic region, by providing a detailed assessment by simulation software showing expectations of each studied material. Finally, the results show that wooden construction materials have the least energy consumption, while single masonry wall construction the highest. This study proved that an insulated wooden wall can provide the least energy consumption spent on space heating when compared to different walls in the cold climate of Lebanon.