Mechanical Engineer

Weston & Sampson; Portsmouth (NH); On-site; USD 85,000 - 130,000; Full time

Benefits offered by this job

Meaningful work

Ownership mindset

Growth opportunities

Flexible workplace

Strong culture

Job summary

Weston & Sampson is seeking an experienced Mechanical Engineer to join our Mechanical HVAC and Plumbing team in New England offices. You will lead design, documentation, and technical leadership for diverse projects, from concept to construction.

You’ll collaborate with engineers across disciplines, manage complex assignments, mentor junior staff, and ensure high-quality, code-compliant solutions while traveling regionally as needed.

Qualifications

• Bachelor's degree in Mechanical Engineering.
• 6–12 years of relevant experience in mechanical design, building systems, plumbing, and/or energy-related engineering.
• Professional Engineer (PE) license.
• Thorough understanding of Massachusetts building codes and familiarity with applicable building codes across other New England states.
• Experience with plumbing systems including DWV design.
• Experience with fire protection systems design.
• Experience with Revit 3D modeling or comparable software, and AutoCAD.
• Ability to work independently and manage complex assignments.

Responsibilities

• Lead design and documentation of mechanical, HVAC, plumbing, fire protection, and energy systems for new and renovated facilities.
• Manage projects from concept through construction documentation and shop drawing reviews.
• Provide technical leadership and ensure code-compliant, constructible designs.
• Coordinate with multi-discipline teams, clients, subconsultants, and vendors.
• Mentor junior staff and review design work to build skills.
• Track multiple projects and maintain schedules and deliverables.

Skills

Mechanical design

Building systems

Project leadership

Mentoring

Revit

AutoCAD

Field investigations

Travel readiness

Education

Bachelor's degree in Mechanical Engineering

Tools

Revit

AutoCAD

Job description

Lead impactful projects. Mentor future engineers. Shape the future of building systems design.

Weston & Sampson is seeking an experienced Mechanical Engineer to join our Mechanical HVAC and Plumbing team in any of our New England offices. This is an exciting opportunity for a motivated professional to take on greater project responsibility, provide technical leadership, and contribute to the continued growth of our engineering practice.

You’ll work on a diverse portfolio of new construction and renovation projects across the private, public, federal, and municipal sectors. Collaborating with multidisciplinary teams, you’ll help develop practical, high-quality engineering solutions while building strong client relationships and supporting the professional development of junior staff.

The ideal candidate brings a strong background in mechanical building systems design, experience working within a multidisciplinary engineering consulting firm, and the ability to independently manage complex assignments from initial concepts through construction documentation. We’re looking for someone who combines technical expertise with sound judgment, effective communication, and a commitment to collaboration and quality.

What You’ll Do

• Lead engineering design and documentation: Develop mechanical, HVAC, plumbing, fire protection, and energy-related designs for new construction and renovation projects across a variety of facility types.
• Manage projects from concept to completion: Conduct field investigations, evaluate existing facilities, prepare engineering reports, develop construction documents, and review shop drawings.
• Provide technical leadership: Apply engineering principles, building codes, and industry standards to develop practical, code-compliant, and constructible design solutions.
• Coordinate across disciplines: Work closely with engineers and design professionals in local and regional offices, as well as clients, subconsultants, utility companies, and equipment vendors.
• Mentor and support junior staff: Provide technical guidance, review design work, and help develop the skills and capabilities of less experienced engineers.
• Manage multiple priorities: Oversee concurrent projects, coordinate detailed building systems requirements, and maintain project schedules and deliverable quality.
• Support client and project success: Communicate technical recommendations, resolve design challenges, and contribute to positive project outcomes throughout the design and construction process.
• Work safely in the field: Participate in site investigations and project meetings at facilities throughout New England and, occasionally, along the East Coast.

What You’ll Bring

• Bachelor's degree in Mechanical Engineering.
• 6-12 years of relevant experience in mechanical design, building systems, plumbing, fire protection, and/or energy-related engineering.
• Professional Engineer (PE) license
• Thorough understanding of Massachusetts building codes and familiarity with applicable building codes across other New England states.
• Working knowledge of plumbing systems, including drain, waste, and vent (DWV) design.
• Experience calculating and designing fire protection systems, including electric and engine-driven fire pumps, cisterns, wet and dry sprinkler systems, and kitchen and other chemical fire suppression systems.
• Experience with Revit 3D modeling or comparable 3D design software, along with AutoCAD.
• Ability to work independently with minimal oversight, coordinate mechanical concepts through implementation, and collaborate effectively with other building systems disciplines.
• Experience managing complex projects and directing or reviewing the work of junior staff.
• Ability to manage multiple concurrent projects and meet deadlines while maintaining a high standard of technical quality.
• Ability to travel locally throughout New England and occasionally along the East Coast for project meetings and site investigations.
• Valid driver's license.

Overview

At Weston & Sampson, you’ll work alongside more than 1,000 employee-owners who are passionate about improving our communities. From providing clean water to designing resilient infrastructure and sustainable environments, our work has a direct impact on quality of life. We’re looking for curious, driven professionals who want to contribute to innovative, impactful projects and grow with a team that supports them.

We are a 100% employee-owned, interdisciplinary firm offering design, engineering, and environmental services. Since our founding in 1899, we have worked to build a collaborative, forward-thinking environment grounded in respectfor each other’s ideas.

We offer

• Meaningful work:Contribute to projects that protect and enhance the natural and built environments
• Ownership mindset: As an employee-owner, your work directly contributes to our shared success
• Growth opportunities: Build your career through mentorship, diverse projects, and clear advancement pathways
• Flexible workplace: Work in a way that supports your life and not the other way around
• Strong culture: Join a team that values collaboration, inclusion, and recognition

Our Commitment to Inclusion, Diversity, Equity & Access (IDEA)

We believe diverse perspectives make us stronger. Weston & Sampson is committed to fostering a culture of belonging where all employees feel valued, respected, and empowered. We actively support IDEA principles across our organization and in our daily work.

Ready to transform your environment? Let’s work together.