The report focuses on the carbon footprint of façades, specifically the significance of glass in reducing the whole life carbon of the built environment. The study was conducted by Arup and Saint-Gobain Glass in partnership, using unique expertise, detailed datasets, industry context, and existing analysis tools. The report presents the findings from a life cycle assessment of 16 façade typologies and 18,000 design simulations, highlighting the influence of design choices on the carbon impact of glass within façades. The report concludes with recommendations for targeted decisions to reduce emissions across supply chains and design processes.