For wave energy to become a commercially viable source of energy, a complete understanding of the wave resource characterisation is needed. In this context, the IEC (International Electrotechnical Commission) has developed a technical specification for the assessment of the wave resource, IEC-TS 62600-101: Marine energy-Wave, tidal and other water current converters-Part 101: Wave energy resource assessment and characterisation (IEC-62600-101), which presents a series of recommendations for standardising wave resource characterisation. The IEC-62600-101 classifies resource assessment studies into three different classes: reconnaissance, feasibility and design. The model setup requirements (mesh resolution, boundary conditions) and the effort (validation process, computational times) vary considerably from one class to the other. On these grounds, the objective of this work is to explore this methodology using the Irish West Coast as a case study. Overall, it was found that the methodology proposed performs well, offering a detailed characterisation of the resource; however, with the aim of making the technical specification more manageable, some aspects related to the seasonality of the wave resource and the validation and model setup procedures may be revisited for future editions.