The increasing need for sustainable and affordable habitats demands innovative strategies in both new build projects and the regeneration of existing facilities. This paper presents an analytical and practice-based study on the use of modular design, digital fabrication, and off-site construction to enhance the smart and sustainable design, construction, and operation of built environments. The methodology combines a comparative analysis of recent studies with a critical review of industry data and policy documents, assessing the environmental, economic, and social impacts of these technologies. The findings reveal that integrating modular and digital construction methods improves resource efficiency, reduces waste, and lowers embodied carbon, while also increasing flexibility in design and shortening project delivery times. Importantly, the research highlights how these approaches can drive social value by improving affordability, reducing on-site disruption, and enabling the rapid delivery of high-quality, adaptable habitats tailored to community needs. This paper frames technical innovation within the wider context of social inclusion and affordability, offering actionable recommendations for designers, policymakers, and developers who aim to achieve equitable and sustainable outcomes in both new construction and regeneration projects. The study concludes with practical strategies for implementing these methods to balance environmental responsibility, cost-effectiveness, and social impact across the built environment sector.