This research explores the impact of passive interventions on various energy consumption parameters and their interdependence to enhance the energy efficiency of a building. While overall outcomes from envelope interventions using passive strategies are positive, a closer examination on an hourly basis reveals certain drawbacks that impede improvements in energy efficiency. A combination of methods is employed, utilizing the gray-box method for input data collection and the white-box method for sensitivity analysis to assess the impact of proposed interventions on building envelope individually and in combination. The building's energy consumption reveals that the combined impact of the passive strategies results in an approximately 82% reduction in gas consumption and a 2% reduction in electric consumption. Sensitivity analysis underscores the necessity of hourly investigations, introducing a research dimension to the study. Hourly assessments expose side effects that hinder the rate of improvement in the envelope retrofitting scenario. Statistical analysis of consumer parameters highlights the significance of the cooling system's hourly consumption, particularly in mitigating undesirable effects during shoulder seasons. By minimizing these side effects, the energy consumption of the cooling system in the envelope retrofitting scenario represent a notable 41.44% reduction, a substantial improvement from the initial 16.16%.