Principal Mechanical Engineer

Principal Mechanical Engineer - HVAC & Building Physics (Remote)

Fully Remote
£60/hr Inside IR35
12-Month Minimum Contract
We're seeking an experienced Principal Mechanical Engineer to support a major defence infrastructure programme delivering critical M&E systems across Building C and Southern Services within the 10 Dock development.
This is a fully remote, long-term contract opportunity focused on HVAC design, substantiation, and multidisciplinary coordination within a highly regulated environment.

The Role
You'll lead mechanical design activities across concept, scheme, and detailed design stages, with particular responsibility for HVAC systems supporting substation infrastructure and occupied operational spaces.

Key responsibilities include:

Delivery of RIBA Stage 3 and Stage 4 mechanical design
HVAC and controls design for critical environments
Design and substantiation of central and local ventilation systems
Chilled water system design supporting electrical plant areas
Coordination of thermal modelling activities and building physics assessments
Supporting FMECA, HAZID/HAZOP, and nuclear safety case activities
Mechanical coordination across multidisciplinary teams
Input into Basis of Design documentation and designer risk assessments
Supporting client liaison, design management, interface coordination, and ECI activities
Additional systems include:

Void ventilation
Gas detection
Heating systems
Cold water services
Project Scope
Building C forms part of the wider 10 Dock facility and includes critical substation infrastructure supporting operational dock systems.
Southern Services provides the M&E connections between Devonport infrastructure and 10 Dock, including:

HV cable routing infrastructure
Mechanical piped service trenches
Incoming and outgoing service interfaces
What We're Looking For

Principal or highly experienced Mechanical Engineer
Strong HVAC and controls background
Experience delivering RIBA 3 and RIBA 4 designs
Good appreciation of building physics and thermal modelling
Ability to coordinate substantiation activities and support safety case requirements

Experience with in complex infrastructure, defence, nuclear, or mission-critical projects advantageous
This is a fantastic opportunity to support a high-profile programme with long-term stability, technically challenging work, and fully remote delivery