Construction Mechanical Engineer II

Relativity Space•Long Beach, CA

About The Position

The Construction Mechanical Engineer II supports the design, development, and delivery of mechanical systems for Relativity Space’s factory and facilities. Systems include HVAC, plumbing, process gas distribution, and specialized systems such as cryogenic, high-pressure, and oxygen monitoring systems. The role performs engineering calculations, equipment sizing, load analyses, and system performance evaluations to support efficient, reliable, and code-compliant designs. The engineer develops and maintains mechanical design documentation, including AutoCAD drawings, Revit models, Basis of Design narratives, technical specifications, and as-built drawings. The role collaborates with engineering, construction, manufacturing, and facilities teams to coordinate mechanical systems, support constructability, and align designs with operational requirements. The position supports mechanical and plumbing projects from concept and design through construction, commissioning, and handoff, including scheduling, budgeting, risk assessment, and documentation. It also reviews external consultant and vendor designs, drawings, and submittals; conducts site inspections; troubleshoots issues; responds to RFIs; coordinates field resolutions; and supports startup, testing, commissioning, and continuous improvement for manufacturing and office facilities.

Requirements

Bachelor of Science degree in Mechanical Engineering or a related engineering field.
At least 2 years of experience in mechanical design and engineering for infrastructure, manufacturing, or commercial building systems.
Experience designing and specifying HVAC, hydronic/chilled water, plumbing, drainage, compressed air, and exhaust systems.
Experience developing Basis of Design documentation, mechanical load calculations, and equipment sizing.
Familiarity with mechanical codes and standards, including ASHRAE, Title 24, NFPA, and the Uniform Plumbing Code (UPC).
Experience creating and reviewing permit-ready mechanical drawings and specifications.

Nice To Haves

Master’s degree in Mechanical Engineering or a related field.
Engineer In Training (EIT) Certification.
LEED GA or LEED AP accreditation.
Background supporting cleanroom ventilation, specialty gas systems, or critical environment design.

Responsibilities

Support design and development of HVAC, plumbing, process gas distribution, and specialized mechanical systems.
Perform engineering calculations, equipment sizing, load analyses, and system performance evaluations.
Develop and maintain AutoCAD drawings, Revit models, Basis of Design narratives, technical specifications, and as-built drawings.
Coordinate mechanical systems with engineering, construction, manufacturing, and facilities teams to support constructability and operational requirements.
Support mechanical and plumbing projects from concept and design through construction, commissioning, and final handoff, including scheduling, budgeting, risk assessment, and documentation.
Review external consultant and vendor designs, drawings, and submittals for compliance with codes, standards, project specifications, and safety requirements.
Conduct site inspections, troubleshoot technical issues, respond to RFIs, and coordinate with contractors and internal stakeholders to resolve field challenges and maintain project timelines.
Support system startup, testing, commissioning, and continuous improvement initiatives to improve facility system efficiency, reliability, and maintainability.