This chapter illustrates how the adoption of a knowledge-based engineering approach may provide a powerful tool for the industrialised house building sector to manage the complex and multidisciplinary nature of design, fabrication and installation. The research focuses on timber technologies and prefabricated timber components, which are frequently selected in preference to other industrialised building systems because of the advantages they offer in terms of weight, workability and sustainability strategies. A knowledge-based engineering methodology is explored for the design of prefabricated timber-framed external walls, encoding both “explicit” and “tacit” knowledge into a digital three-dimensional model. Results demonstrate how such an approach could significantly change common design practices by shifting the major phase of design effort to earlier stages in the project cycle, thereby minimising re-work, reducing data fragmentation and potentially removing the need for drawings. A key finding of this paper is that model interoperability, maintenance and reuse becomes unlikely if an agreed methodology, including a description logic, is not adopted. Despite the need for a rigorous approach, the ability to capture, manage and reuse design knowledge could be of significant benefit to emerging industrialised house building ventures.