Early-Stage Massing Decisions in School Buildings: Interactive Effects on Energy and Thermal Comfort Performance

Early-stage architectural decisions strongly condition long-term energy demand and thermal comfort; however, their combined effects are often evaluated in isolation. This study investigates the interactive influence of mass configuration, orientation and the window-to-wall ratio (WWR) on the energy and thermal comfort performance of school buildings in Erbil, Iraq. Five representative school mass typologies were assessed using a structured two-phase simulation framework based on an Interactive Architectural Approach (IAA). The results reveal that mass configuration functions as a conditioning variable, governing not only absolute energy demand but also responsiveness to design variation. Articulated typologies showed amplified increases in cooling demand, overheating, and mean radiant temperature under a higher WWR, whereas compact forms exhibited comparatively stable behavior. Importantly, orientations minimizing energy demand did not consistently correspond to those minimizing thermal discomfort, revealing typology-dependent divergence between performance objectives. By quantifying interaction-based sensitivity rather than isolated parameter effects, the study advances IAA as a structured early-stage assessment framework for school design.