Principal Mechanical Design Engineer in London

Our Client is a forward–thinking independent building services design and build contractor delivering sustainable, innovative, and technically robust engineering solutions across the built environment. They pride themselves on high–quality MEP preconstruction and installation services, engaging with customers to meet expectations and deadlines.

The demand for M&E pre–con services continues to grow annually and with a heightened desire to keep more design projects inhouse, this will naturally reduce the reliance of framework consultants who provide detailed design assistance when required. With this goal in mind, the business is looking to hire as a priority a Principal Mechanical Design Engineer to lead complex design projects and support the strategic development of inhouse mechanical engineering capabilities.

The Principal Mechanical Design Engineer will take a lead role in the design, delivery, and technical oversight of mechanical building services projects. The position combines hands–on design work with project leadership, client management, and mentoring of the Junior Engineers. The successful candidate will ensure the delivery of high–quality, compliant, and energy–efficient systems across a diverse portfolio of projects including hotels, gyms, and offices, along with industrial and residential developments.

• Lead the mechanical design on projects from feasibility through to detailed design and construction stages.
• Produce and review mechanical design calculations, reports, specifications, and drawings.
• Oversee the integration of HVAC, public health, heating, cooling, ventilation, and sustainable technologies into building designs.
• Ensure designs meet industry standards, regulatory requirements, and company quality benchmarks.
• Conduct technical reviews, design audits, and value engineering exercises.
• Manage project deliverables, timelines, budgets, and resource allocation.
• Attend client and design team meetings, providing clear technical guidance and updates.
• Support tender packages, technical submissions, and contractor queries.
• Act as a trusted advisor to clients, building and maintaining strong relationships.
• Mentor and support Junior Engineers in their technical and professional development.
• Provide guidance on standards, best practices, and innovation in mechanical design.
• Contribute to internal knowledge sharing and continuous improvement initiatives.
• Promote low–carbon design principles and integrate renewable technologies where appropriate.
• Stay up–to–date with industry trends, legislation, and emerging technologies.
• Drive innovation in design tools, workflows, and sustainable engineering practice.

• Degree in Mechanical Engineering or Building Services Engineering (or equivalent).
• Substantial industry experience in mechanical building services design within a consultancy or contracting environment.
• Proven experience leading and managing complex MEP projects.
• Strong understanding of UK Building Regulations, CIBSE guides, BSR compliance, and relevant standards.
• Proficiency in design software such as Hevacomp, IES VE, Revit MEP, and AutoCAD.
• Excellent communication, report writing, and client–facing skills.
• Knowledge of digital engineering, BIM processes, and modern design workflows.

This position would best suit an HVAC Design Engineer looking for a genuine leadership role, capable of taking on significant responsibility. Reporting directly to the owners and shareholders, the position also carries the potential for rapid self development and the opportunity to work towards your own career objectives.