Metal additive manufacturing has been applied across various fields, including medicine and aerospace, with its potential now being recognised in the construction industry. Recently, Wire Arc Additive Manufacturing (WAAM) has been used in several structural applications, such as strengthening and repairing existing components, as well as producing parts with geometric complexities, often featuring thin-walled structures. However, the technology is believed to offer even greater potential for fabricating larger components with more complex geometries, providing enhanced structural benefits. This paper first examines the mechanical properties of normal strength structural steel (ER70S-6) fabricated through WAAM, employing a series of tensile and compressive coupon tests. Secondly, the geometric imperfections are characterised and an idealised model is proposed. Furthermore, fracture parameters are characterised using the established Lode Modified Void Growth Model (LMVGM), enabling a comprehensive understanding of the material’s behaviour across the entire deformation range.