Senior Mechanical Engineer

Senior Mechanical Engineer (Hybrid)

At Salas O’Brien we tell our clients that we’re engineered for impact. This passion for making a difference applies just as much to our team as it does to our projects. That’s why we’re committed to living our values every day: inspiring, achieving, and connecting as shared owners of our success with a focus on a sustainable future.

Building for the long‑term means that all of our team members can expect to work on amazing projects with a people‑first approach to problem solving. It also means that each member of our team has truly limitless potential to build a unique, meaningful, and high‑impact career—and they’ll receive great total rewards along the way.

The Senior Mechanical Engineer leads the design, coordination, and delivery of complex building HVAC and thermal energy systems. This role provides technical leadership across heating, cooling, ventilation, and control systems while managing multidisciplinary design teams and working directly with clients. Candidates with extensive HVAC systems design experience or deep expertise in building energy modeling and life‑cycle cost analysis are encouraged to apply.

• Lead the design and delivery of complex HVAC and thermal energy systems across all project phases
• Provide technical leadership, mentorship, and quality oversight to mechanical design teams
• Design and coordinate thermal energy generation and distribution systems, including hot water, steam, chilled water, geothermal well fields, water‑source and air‑source heat pumps
• Perform and oversee engineering calculations to determine HVAC system loads using IESVE or similar tools
• Design HVAC systems including air handling, energy recovery, precision temperature and humidity control, and radiant heating and cooling
• Develop building automation and control strategies to support performance, efficiency, and occupant comfort
• Prepare mechanical master plans and support long‑term infrastructure planning
• Support sustainable design initiatives and certification efforts, including LEED, LBC, PHIUS, and WELL
• Collaborate with architects, owners, utilities, and contractors to resolve technical challenges
• Participate in client meetings, presentations, and interdisciplinary coordination efforts

• Bachelor of Science in Mechanical Engineering (BSME) required
• Ideally minimum of 10 years of experience designing and leading design teams for building HVAC systems
• Professional Engineer (PE) license preferred
• Demonstrated experience with complex HVAC and thermal energy systems (required)
• Proficiency with IESVE or similar HVAC system load calculation software required
• Strong written and verbal communication skills, with comfort in client‑facing environments
• Proven ability to manage multiple projects, priorities, and stakeholders

Laconia, NH / Boston, MA / Portland, ME

Hybrid

Up to 20%

The expected base salary range for this role is $110,000 - $150,000 USD per year. Actual compensation will be determined based on a number of factors including skills, experience, qualifications, and location.

This role is also eligible for performance-based bonuses and a comprehensive U.S. based benefits package, including:

• Medical, dental, and vision insurance
• 401(k) with company match
• Paid time off and company holidays
• Wellness programs and employee assistance resources
• Professional development support

For more information, visit our full benefits overview here.

Founded in 1975, Salas O’Brien is an employee‑owned engineering and professional services firm focused on achieving impact for our clients, our team, and the world. We know that tomorrow’s requirements are today’s opportunities, and we are here to design lasting solutions for pressing challenges.

We work across a variety of industries providing integrated engineering and consulting services. Our specialized experience includes design for data centers, healthcare, science and technology, high‑rise buildings, clean energy, education, and other building types as well as structural and building sciences, infrastructure asset management, advanced robotics,…