Exploring the Impact of Span Length on Environmental Performance: A Comparative Study

Architects and building designers are pivotal in mitigating climate change by shaping the environmental footprint of buildings from their inception, with life cycle assessment (LCA) serving as a crucial tool for quantifying these impacts. Given that structural systems contribute significantly to embodied carbon, accounting for approximately 24% of a building’s life cycle emissions, this research investigates the relationship between structural span length—a key design factor influencing material choices and construction methods—and overall environmental performance. Through a scenario-based analysis employing building information modeling (BIM) and whole building life cycle assessment (WBLCA) tools, this study evaluates various building configurations to reveal that in long-span scenarios, steel demonstrates a lower environmental impact compared to timber. This finding offers a novel, quantifiable insight for architects and designers to assess and optimize building designs, particularly in the context of emerging architectural trends featuring longer spans, ultimately contributing to more sustainable building practices.