Mechanical Design Manager - Main Contractor (Residential Projects)
Location: London & Surrounding Areas
Type: Permanent | Full-Time
Salary: £80,000 + Package

About the Company

We have a vacancy with an established Main Contractor who have a strong reputation for delivering high-quality residential developments across London and the South East. Their clients include major developers and local authorities, with projects ranging from mid-rise apartment schemes to large-scale regeneration developments. As their project pipeline continues to grow, they are seeking a Mechanical Design Manager to join their in-house team.

The Role

This is a key technical role, responsible for overseeing the mechanical design process from initial client brief through to delivery on site. The Mechanical Design Manager will take ownership of early-stage engineering input, ensuring all designs meet regulatory, safety and performance standards, with a specific focus on compliance with Building Safety Act requirements, including Gateway 2 and Gateway 3.

Working closely with external consultants and the internal project delivery team, you will review and verify design calculations, manage the flow of technical information, and coordinate with M&E subcontractors during the installation phase.

Key Responsibilities

• Develop and interpret client briefs into high-level mechanical engineering strategies.
• Carry out preliminary engineering calculations such as heat loss/gain, pipe sizing, and flow rate assessments.
• Act as the technical lead through RIBA Stages 3 to 5, ensuring compliance with current regulations, including Gateway 2 and Gateway 3 requirements under the Building Safety Act.
• Manage and coordinate the production of mechanical design documentation by external consultants.
• Review and verify mechanical designs, calculations, and specifications to ensure accuracy, feasibility, and compliance.
• Provide technical input and oversight during the procurement and management of the M&E subcontractor supply chain.
• Support the site team during installation, testing, commissioning, and handover phases.
• Liaise with building control, client representatives, and design stakeholders throughout the project lifecycle.

Requirements

• Demonstrable experience in mechanical design management within the residential sector, ideally with a Main Contractor or design consultancy.
• Strong understanding of building services design and performance requirements for residential developments.
• Full working knowledge of Gateway 2 and Gateway 3 under the Building Safety Act, and experience ensuring design compliance at these stages.
• Competent in engineering calculations and principles for heating, ventilation, water systems, and energy efficiency.
• Proven track record of managing external design consultants and subcontractor coordination.
• Familiarity with relevant regulations and industry standards, including CIBSE guidelines, Building Regulations Part L, and sustainability standards.
• Excellent communication, coordination, and stakeholder management skills.

Package & Benefits

• Competitive salary dependent on experience
• Car allowance or travel expenses
• Private healthcare and pension scheme
• Clear career progression within a growing business
• Involvement in major residential developments across London

To Apply
To discuss the role in confidence or apply directly, contact the team at 12 Recruitment today.