The thesis explores energy retrofitting options for enhancing the energy efficiency of residential buildings in Jeddah, Saudi Arabia. It identifies and validates cost-effective energy retrofit schemes that have the potential for energy savings. The thesis also assesses the feasibility of energy retrofitting scenarios for building envelopes and their impact on reducing energy consumption, improving thermal comfort, and mitigating the environmental impact of buildings. The results of this research can guide architects and decision-makers on energy-saving measures for residential buildings in Saudi Arabia, with Jeddah serving as a representative case study.@en

Residential buildings in the Kingdom of Saudi Arabia (KSA) contribute to nearly half of the overall electricity consumption in the building stock, highlighting their significant role in energy consumption. While an upgraded energy code has been established and enforced for new buildings, existing buildings continue to operate at the same level of energy consumption. Therefore, there is a need for further energy upgrades in existing buildings. This study evaluates the energy savings potential of various energy retrofitting measures for a case study in Jeddah, KSA. Data from previous studies and current practices were collected and analyzed. Different energy upgrade measures, such as windows replacement, wall insulation upgrade, roof insulation upgrade, and air conditioning unit replacement, were selected and evaluated using a digital simulation tool called Design-Builder. The simulation results were compared to understand the potential percentage of energy savings. The average annual energy consumption (AAEC) was used as the primary performance indicator to compare the energy savings among the scenarios. The results demonstrate significant reductions in energy consumption for the proposed scenarios. Furthermore, the study examined the significant impact of uncertainties, specifically, the infiltration rate and AC setback temperature, on AAEC. In conclusion, the proposed scenarios have the potential to achieve substantial energy savings, ranging from 25% to 66%, depending on the number of energy retrofitting interventions employed. The findings of this study can serve as a useful reference for similar energy retrofitting projects.@en

In the Kingdom of Saudi Arabia (KSA), residential buildings' energy consumption accounts for almost 50% of the building stock electricity consumption. The KSA's economy relies heavily on fossil fuel sources, namely oil reservoirs, whose depletion will negatively affect the future development of the country. The total electricity consumption is growing by approximately 5-8% annually, which would lead to oil production and oil consumption being equal in 2035. Therefore, residential buildings need further assessment as regards their current energy consumption. This research used a survey to explore current user behaviour in residential buildings' energy performance in the city of Jeddah, KSA. The findings of the survey show that several factors impact the energy performance in residential buildings. First, the buildings' thermal properties were found to be poorly designed. Second, the cultural aspects (family member role and generous hospitality), and the majority of users within the buildings preferring a room temperature of below 24 • C, requires a massive amount of cooling due to the climate conditions. Third, an increase in user awareness has helped to slightly improve residential buildings' energy efficiency. Knowing the current high-energy-consumption sources and causes, being able to define opportunities for thermal properties' enhancement, and increasing user awareness of how to achieve self-sustaining buildings are essential.@en