Advanced manufacturing technologies offer significant opportunities in reducing time, cost, and waste (positive environmental and economic advantage) for future nuclear new build, especially for small modular reactors (SMRs), where modularization and standardization of SMRs will enable factory production, moreover improving social sustainability due to cleaner ways of manufacturing and influencing positive impact on employees. Electron beam welding (EBW) at the Nuclear AMRC (Nuclear Advanced Research Centre) has demonstrated to produce a range of joints in a fraction of the time required by submerged arc welding (SAW), while eliminating the use of filler materials and without generating non-recyclable slag. Near-net shape techniques, such as hot isostatic pressing (HIP), have been successfully demonstrated by EPRI (Electric Power Research Institute) to produce large components which will enable a new supply chain to support global steel producers for large castings and forgings to meet expected future demand of the energy sector. Similarly, improved resource efficiency and reduced energy consumption and waste generation are increasingly important considerations in manufacturing alongside time and cost. The Nuclear AMRC conducted a sustainability assessment study of the joining technologies, focusing on energy consumption, and waste generation. Understanding the potential environmental, economic, and social benefits of advanced technologies is essential for strengthening their application in the nuclear sector.