Senior​/Principal Mechanical Design Engineer

Senior to Principal Mechanical Design Engineer | Oxford | Low Carbon Projects, Heritage Refurbishments, Progression Opportunity

A well‑established, independent building services consultancy in Oxford is looking to strengthen their mechanical team with an experienced Senior or Principal Mechanical Engineer.

Known for delivering technically robust, sustainable solutions across heritage, education, healthcare, and infrastructure projects, this team combines mechanical, electrical, lighting, Passivhaus, and building physics expertise under one roof. With a strong pipeline of work and ongoing investment in their people, this is a great opportunity to step into a high‑impact role with long‑term progression potential.

• Lead or support mechanical design from RIBA Stage 2 through to handover, including detailed HVAC, hot and cold‑water systems, and sustainable design strategies
• Collaborate with clients, architects, and internal teams to develop low‑energy, technically sound solutions across new‑builds and complex refurbishments
• Apply building performance analysis and building physics principles where relevant, working closely with in‑house specialists
• Oversee or contribute to technical documentation, drawings (AutoCAD, Revit), and specifications
• Attend site visits, manage design coordination, and provide support throughout the construction phase
• Mentor junior engineers and take an active role in internal knowledge sharing
• At Principal level, contribute to fee proposals, resourcing, and client development

• Degree‑qualified in Mechanical Engineering or Building Services (or similar)
• 6+ years of experience in a consultancy environment delivering mechanical design
• Experience working on projects in sectors like education, commercial, healthcare, or heritage
• Excellent technical understanding of HVAC systems, regulations, and energy‑efficient design
• Familiarity with Revit, AutoCAD, IES or Hevacomp (or similar design tools)
• Strong communication and coordination skills
• Chartership (CEng MCIBSE) or working towards it is desirable

• Competitive salary based on experience, typically between £55,000 and £70,000 for this level
• A broad project portfolio with real design variety, including listed buildings and modern low‑energy campuses
• Flexible/hybrid working, 25+ days holiday, private healthcare, cycle to work scheme, CPD support, and more
• A collaborative, technically strong team with a great culture and low staff turnover
• Structured progression path to Associate and beyond, with support toward chartership and leadership development

If you're a Senior or Principal Mechanical Engineer looking for meaningful, sustainability‑focused work with room to grow, this is an opportunity well worth exploring.