Principal Mechanical Engineer (Data Centre)

Job Description

Principal Electrical Engineer - Data Centres\n\nUp to £70,000 + Benefits \n\nCentral London Flexible Hybrid\n\nAn established UK engineering consultancy-independent for over 70 years- is expanding its specialist Data Centre team and is seeking a Principal Mechanical Engineer with strong technical design experience. This is an opportunity to join a respected, people-centric business with an average staff tenure of 12 years, a genuine open-door culture, and a commitment to continuous progression without rigid promotion cycles.\n\nWhy Join?\n\nA genuinely supportive culture\n\nNo annual reviews or fixed pay-rise cycles - promotions and salary increases happen as soon as they're earned.\n\n"No stupid questions" philosophy - learning is encouraged and supported.\n\nHighly selective hiring focused on technical excellence, ensuring you work alongside capable, high-quality engineers.\n\nFlexible hybrid working: 2 days in the office (Tue/Thu typically; 3 days initially for onboarding and collaboration).\n\nLong-standing leadership that trusts its engineers and provides autonomy.\n\nStrong Benefits Package\n\n25 days holiday + Christmas shutdown (rising to 28 after 6 years)\n\nContributory private healthcare\n\nStandard pension\n\nEAP including financial & legal support\n\nAnnual wellbeing day: a full team day out (walks, tours, social events)\n\nChartered Engineer mentorship available (including from a recognised CIBSE Data Centre leader)\n\nAbout the Data Centre Team\n\nThe London-based Data Centre group consists of a core team of five permanent engineers, supported by contractors when needed. The team is led by senior Electrical and Mechanical leads, with a strategic plan to continue growing a central London hub before expanding expertise across other UK offices.\n\nThe practice has made a deliberate and successful push into the data centre sector over the last two years, securing work with major global operators (hyperscalers and colocation providers).

While most work is UK-based, they are now being asked to support clients on European projects.\n\nProject & Technical Exposure\n\nYou will work on both design and technical advisory projects, including:\n\nStrategic asset replacement programmes\n\nNew build data centres up to 100MW\n\nReviewing and upgrading live MEP systems in operational facilities\n\nCompliance monitoring\n\nDetailed Mechanical design, specifications and scopes of work\n\nThis role is hands-on and design-focused - not a project management position (although PM skills can be developed).\n\nWhat They're Looking For\n\nSenior or Principal-level Mechanical Engineer with strong data centre design experience\n\nSolid understanding of critical Mechanical infrastructure and MEP integration\n\nCapable of delivering high-quality technical work and contributing to client-facing advisory tasks\n\nSomeone who values autonomy, collaboration, and technical excellence\n\nUK-based, able to attend the London office twice weekly\n\nThe consultancy does not use salary bandings and pays based on technical capability - up to £75k is realistic for a strong Principal.\n\nIf you're an Mechnically biased Data Centre specialist looking for a technically engaging role within a supportive, low-ego engineering environment, this position offers long-term growth, high-profile project exposure, and the chance to help shape a growing specialist team.\n\nCalibre Search promote equality in the workplace and we welcome applications from all suitably skilled or qualified candidates regardless of their , , , religion/beliefs, or . We act as both an employment agency and employment business