In sustainable construction, the relationship between carbon and cost is rarely straightforward. Decisions made at the earliest stages of a project, often before the full scope is defined, can lock in both environmental impact and financial trajectory. From site selection and massing to internal layout, each choice influences embodied carbon, operational efficiency, and long-term value. Yet sustainability and cost are still too often treated as opposing forces rather than interconnected levers.

Together, the structural frame and foundations typically represent most of the upfront carbon emissions for new office buildings. Commissioned by the British Constructional Steelwork Association, this article examines how different structural solutions perform across carbon and cost metrics, and why strategic alignment during early design stages is critical.

To support this study, Aecom’s Eco.Zero™ Concept carbon and cost optioneering tool enabled analysis beyond generic benchmarks to generate outputs grounded in structural design data. This tool facilitates deeper analysis of how column grids, material choices and layout strategies affect both embodied carbon and capital cost. As with any early-stage quantification tool, it relies on certain assumptions and simplifications, such as regular column grids, uniform loading and consistent ground conditions. Still, the insights it provides help inform smarter, lower-carbon decisions at the project outset when flexibility is highest and impact is greatest.

Sustainable design begins with the recognition that reusing and refurbishing existing structures should always be the first consideration. Where new construction is required, structural options must be evaluated through a lens that extends beyond carbon alone to include cost, material intensity and circularity. To that end, this analysis focuses on the structural frame as a key component of the broader sustainability picture.

Read more…