Evaluating the Sensitivity of Air Infiltration Rates on Envelope Thermal Insulation Performance

High energy demands and greenhouse gas emissions have increased globally, prompting the development of energy-efficiency frameworks, legislation, and housing approvals. Due to extremely hot climatic conditions, Saudi Arabia is a primary energy producer and consumer. According to the Saudi Efficiency Center, cooling energy accounts for about 70% of the residential sector’s energy demands. Although the government has issued building codes to improve overall energy efficiency and mandated the building envelope's thermal insulation, insulation performance may vary significantly when infiltration rates are not adequately evaluated. The effect of the air infiltration rate on thermal insulation performance in building envelopes is a critical factor in reducing energy demands and carbon emissions. Therefore, this study evaluates the effect of the air infiltration rate on the performance of various types of thermal building insulation using the EnergyPlus simulation tool. The findings indicate that an increased infiltration rate lowers thermal insulation efficiency and raises the indoor air temperature. Positive linear correlations were detected between an increased infiltration rate and insulation efficiency in the Jazan region, regardless of the season and insulation type. This research emphasizes the need to apply effective air sealing and waterproofing to reduce heat gains and mitigate the effect of the infiltration rate on thermal insulation performance.