As an engineering consultancy company involved in large infrastructure projects globally, COWI has the responsibility of recommending the use of materials that are suitable for the projects that match the sustainability ambitions of both client and COWI and, more importantly, that contribute to shaping a sustainable and livable world. This requires us to develop a clear understanding on how to account for the carbon profile of wood as a construction material. This study was thus conducted internally across different departments to determine what methodological choices can provide a solid comparison on the life cycle carbon performance of wood as a primary construction material in large infrastructure. Three different life cycle assessment (LCA) studies were conducted to compare a timber road bridge designed by COWI against a more traditional reinforced concrete design, and differences in the options’ climate impact across the three different methodologies were observed.