Parametric Analysis of Facade Characteristics and Natural Ventilation Strategies in a Budapest Office Building

Abstract

This study investigates the impact of window glazing, window-to-wall ratio (WWR), natural ventilation strategies, and shading on energy efficiency and lighting performance in a case study office building in Budapest, Hungary. Using DesignBuilder software for building performance simulation, various configurations of double and triple glazing, with and without shading, are analyzed across WWRs of 10% and 50%. The study evaluates heating, cooling, and lighting energy consumption to identify design strategies that optimise energy performance and visual comfort. Results indicate that triple glazing with shading and a 50% WWR delivers the most efficient performance by reducing electricity consumption through effective solar heat gain control and enhanced daylighting. In contrast, unshaded large glazing areas lead to higher cooling demand, decreasing overall efficiency despite improved daylight access. Additionally, the study examines three natural ventilation strategies for summer: (1) constant ACH of 0.5 during day and night, (2) high daytime ACH with minimized nighttime ACH, and (3) continuous high ACH. Findings show that the second strategy provides the best thermal comfort but results in the highest energy use, while the first scenario achieves the lowest energy consumption at the expense of comfort. The third approach offers a balanced compromise between comfort and energy performance. These findings highlight the importance of combining façade design elements with appropriate ventilation strategies to maintain thermal comfort and reduce energy consumption in office buildings.