The UK-built environment sector faces significant challenges in reducing greenhouse gas emissions to meet the net zero 2050 targets. Currently, the built environment sector accounts for 40% of carbon emissions globally, and about 39% of UK carbon emissions stem from construction activities. Despite ongoing efforts, carbon emissions levels in the built environment sector remain exceedingly high. Therefore, to address this issue, this research paper aims to identify the carbon assessment challenges in the built environment sector and mitigate embodied carbon in building construction. A systematic literature review will first be employed to investigate the critical challenges of balancing environmental management in smart building construction. Subsequently, an expert interview will be conducted to gather deeper insights. Reducing embodied carbon emissions in the construction of smart buildings presents a variety of intricate issues. These include rising building prices, a lack of low-carbon materials readily available, insufficient government regulations, opposition to novel building materials, a scarcity of experts with an environmental conscience, and a failure to include low-carbon elements in early project stages. These problems are made worse by the absence of rigorous carbon management strategies and environmental impact studies at the project’s inspection. The literature suggests the drivers for effective embodied carbon management within the UK built environment sector to tackle the identified challenges. The recommendations are expected to mitigate the negative environmental impacts and drastically cut embodied carbon emissions. Therefore, this study demonstrates that the built environment sector can make significant progress towards a low-carbon economy and the achievement of net zero 2050 targets.