The application of light steel framing in rapid construction has shown a significant growth, especially in low and medium-rise buildings. Design of joint plays an essential role in structural steelwork. However, for beam-to- column joint design, recent codes of practice show inadequate formulation for moment-rotation prediction as compared to actual connection performance in cold-formed steel design that exhibits large deformation. This book aims to develop numerical models using numerical approach and study the mechanical behaviour of the connection with various parameters. A numerical study with verified and validated modelling configuration is carried out to simulate various geometrical parameters that are not included in the experimental works. As compared to BS EN1993-1- 8 model, the developed model has shown a significant difference. The moment-rotation behaviour was obtained from the developed numerical models for further analysis. An exponential equation with two elastic rotational stiffness, namely PM1 and PM2 has been proposed to improve the mechanical prediction of BS EN1993-1- 8. The design procedure for light steel framing with bolted top-seat flange cleat connection has been proposed. It includes large deformation of cold-formed steel joint, subsequently in which research of light steel framing is still lacking.