Job Description What will you be doing? ALTEN UK is seeking skilled and motivated HVAC Designers / 3D Modelers to support the HPC Nuclear Island project, contributing to one of the most significant low-carbon energy programmes in the UK. This design-focused role involves the 3D modelling and integration of HVAC systems within a nuclear facility, offering you the opportunity to work on high-integrity, safety-critical infrastructure in collaboration with international teams. Your main responsibilities will be: Design and model HVAC systems in 3D using SolidWorks, in accordance with nuclear industry standards Develop and maintain accurate models, layouts, and assemblies for HVAC networks within the facility Collaborate closely with mechanical and multidisciplinary engineering teams to ensure integration of systems Generate supporting documentation including detailed drawings, bills of materials (BoMs), and installation guidance Conduct design reviews and address technical queries or non-conformities throughout the project lifecycle Ensure all work complies with safety, quality, and regulatory requirements Travel to international sites (including Finland and the US) for training, coordination, and design alignment activities You are Passionate about engineering Detail-oriented and quality-driven A strong communicator and effective team collaborator Desirable Skills: Previous experience in the nuclear, energy, or heavy infrastructure sectors Familiarity with BIM workflows and product data management (PDM) systems Ability to convert between metric and imperial units for cross-border coordination