Senior / Principal Mechanical Design Engineer – Building Services
📍 Location: South Wales | 💰 Salary: Competitive + Package
📅 Job Type: Full-time, Permanent
Lead Mechanical Design, Mentor Talent, and Deliver High-Quality Projects
A well-established and highly respected Building Services Contractor in South Wales is seeking a Senior / Principal Mechanical Design Engineer to strengthen their in-house mechanical design team. With a strong pipeline of projects across commercial, education, healthcare, residential, hospitality, and retail sectors, this is an exciting opportunity to take a leadership role with real responsibility.
You’ll join a supportive team delivering technically challenging and rewarding projects, from multimillion-pound new builds to complex refurbishments, while having the chance to mentor junior engineers and shape the future of the department.
Key Responsibilities
Lead mechanical design on projects from concept through to completion
Attend and chair design and coordination meetings with internal and external teams
Act as the main point of contact for clients, representing the business professionally
Ensure all designs comply with UK building regulations, CIBSE guides, and industry standards
Develop detailed designs using software such as Hevacomp, IES, Revit, and AutoCAD
Review and oversee drawings, schematics, and specifications
Mentor and support junior engineers, apprentices, and wider design staff
Report project progress to the M&E Design Director
Collaborate with the in-house construction team and multidisciplinary stakeholders
What We’re Looking For
Degree or HNC/HND in Mechanical or Building Services Engineering (or similar)
Proven experience in mechanical building services design, ideally within a contractor or consultancy
Strong technical knowledge of HVAC, LTHW/CHW systems, and sustainable design principles
Competence with design software (Revit, IES, AutoCAD, Hevacomp)
Ability to lead projects, take ownership of delivery, and work within budgets
Good commercial awareness and client-facing skills
Experience in a contracting environment is advantageous, but training can be provided
Why Join?
Secure, long-term role with a company that invests in its people
Competitive salary and benefits package, negotiable depending on experience
Flexible working arrangements where required
Exposure to a wide range of technically challenging projects
Real autonomy and the opportunity to influence the growth of the design function
Supportive environment with clear progression opportunities
If you’re a Senior / Principal Mechanical Design Engineer looking to take the next step in your career or work on high-quality projects within a company that values its people, apply now or get in touch for a confidential conversation