Senior to Principal Mechanical Design Engineer – Building Services Southampton (Hybrid Working) Full-Time Highly Competitive Salary Bonus Benefits About the Role A leading independent building services consultancy on the South Coast is seeking a Senior to Principal Mechanical Design Engineer to join their growing team in Southampton. Known for their technical strength, sustainable approach, and long-term client relationships, this firm delivers a broad range of projects across the healthcare, education, research, commercial, and industrial sectors. This role is ideal for an experienced engineer ready to lead projects, manage teams, and play an integral part in delivering innovative and low-carbon mechanical building services solutions. What You’ll Be Doing Lead mechanical design on a range of complex projects, from early-stage feasibility to technical delivery and handover Take ownership of project outputs including reports, calculations, technical specifications, and coordinated drawings Collaborate closely with multidisciplinary teams including electrical, sustainability, and BIM engineers Represent the consultancy in client, design team, and contractor meetings Provide mentorship and technical oversight to junior and intermediate engineers Deliver solutions that incorporate sustainable and renewable technologies, complying with relevant legislation and environmental targets Oversee resource planning, programme delivery, commercial aspects, and QA compliance on your projects Contribute to technical standards, internal knowledge sharing, and continuous improvement across the team What You’ll Bring Degree qualified in Mechanical or Building Services Engineering (BEng, MEng, or equivalent) Typically 7 years of experience in mechanical building services design In-depth knowledge of HVAC, public health systems, plant room layout, and system integration Experience using mechanical design tools (Hevacomp, IES, Revit, AutoCAD, etc.) Up-to-date understanding of UK building regulations, CIBSE standards, and sustainability drivers Chartered or working towards CEng status with CIBSE or IMechE A track record of leading design teams and delivering high-quality projects Confident communicator with a client-focused mindset and excellent coordination skills Comfortable balancing design detail with project management responsibilities Why You’ll Want to Join Work with one of the region’s most established independent MEP consultancies Flexible and hybrid working arrangements that promote a healthy work-life balance Diverse project exposure across hospitals, education campuses, science labs, and heritage refurbishments Clear progression routes toward Associate/Director level roles Attractive benefits package, including: 28 days’ annual leave bank holidays Annual performance bonus Private medical cover & life insurance Enhanced pension scheme Cycle to work scheme Annual training allowance and full support to achieve chartership Supportive, people-first culture focused on long-term success and technical excellence Looking to lead high-impact projects and mentor the next generation of engineers? This is an ideal opportunity for a Senior or Principal Mechanical Engineer ready to make a meaningful step in their career. Apply now for a confidential chat.