Senior Residential Mechanical Designer

PEG, LLC • Fairfax, VA

5d • Hybrid

About The Position

PEG, LLC is hiring a Senior Residential Mechanical Designer to provide senior-level technical leadership for residential HVAC design projects. The role is based in PEG’s main office in Fairfax, Virginia, with the option of a hybrid remote/office schedule. The designer will help ensure project quality, efficiency, code compliance, and technical excellence while supporting PEG’s work in high-performance, sustainable residential design.

The position leads and reviews HVAC load calculations, duct sizing, ventilation strategies, and equipment sizing; performs advanced quality reviews of mechanical designs and energy-modeling deliverables; manages project scopes, schedules, and documentation; and coordinates technical matters with internal teams, clients, builders, architects, and other stakeholders. The role also supports process improvements and company best practices, and trains and mentors team members. A bachelor’s degree in Mechanical Engineering or a related field and at least three years of relevant residential HVAC design experience are required. An EIT is strongly encouraged, with a salary incentive offered for obtaining it.

Requirements

• Bachelor of Science degree in Mechanical Engineering or a related field.
• At least 3 years of relevant experience in residential mechanical (HVAC) design.
• Advanced proficiency and experience with AutoCAD.
• Advanced proficiency and experience with HVAC load calculations.
• Advanced proficiency using WrightSoft or similar residential HVAC design software.
• Advanced understanding of ACCA Manual J, Manual D, and Manual S methodologies.
• Strong working knowledge of IECC, ENERGY STAR®, and state residential energy code requirements.
• Advanced proficiency in Excel and SharePoint.
• Strong attention to detail and accuracy.
• Ability to meet deadlines and manage multiple projects simultaneously.
• Efficient time-management and organizational skills.
• Effective interpersonal and collaboration skills.
• Excellent verbal and written communication skills.
• Ability to read, write, and comprehend technical instructions and documentation.
• Strong analytical and problem-solving abilities.
• Ability to work independently with minimal oversight while supporting team development.

Nice To Haves

• EIT; strongly encouraged, with a salary incentive offered to those who obtain it.
• Experience working with green building programs and high-performance residential construction.

Responsibilities

• Lead the preparation, review, and validation of HVAC load calculations, duct sizing, ventilation strategies, and equipment sizing in accordance with ACCA Standards and applicable energy codes.
• Serve as a senior technical resource for the analysis and design teams.
• Perform advanced QA/QC reviews of residential mechanical designs and energy-modeling deliverables.
• Identify design, compliance, or workflow issues and communicate recommendations and resolution options to management.
• Manage complex project scopes by organizing deliverables, milestones, and priorities.
• Establish and maintain project timelines, adjusting schedules proactively as project demands and conditions change.
• Develop technical solutions and process workarounds to maintain project progress and quality standards.
• Coordinate and validate design relationships with internal departments, clients, builders, architects, and other project stakeholders.
• Interpret client requirements, jurisdictional constraints, and project-specific design considerations.
• Use and adapt to industry software platforms, including Manual J Software, AutoCAD, Wrightsoft/Wrightdraw, RESCheck, REM/Rate, and emerging technologies.
• Maintain and manage project documentation, calculations, and reporting through Excel, SharePoint, and internal systems.
• Interface with Operations, Owners, Builders, and Subcontractors to resolve technical issues and communicate project impacts.
• Maintain advanced knowledge of current IECC requirements, state energy codes, and residential mechanical design standards.
• Support development and implementation of internal best practices, templates, and process improvements.
• Train and mentor junior and mid-level team members on technical procedures, software applications, code compliance, and company standards.
• Assist with onboarding and technical development initiatives for new staff.
• Participate in continuing education, certifications, and professional development related to residential HVAC design and green building practices.

Benefits

• 20 annual paid days off: 12 days of PTO, birthday PTO, and 7 company-paid holidays.
• Company-sponsored medical insurance, including a contribution of up to 50% of the monthly premium.
• Dental insurance.
• Vision insurance.
• 401(k) retirement plan with up to a 4% company match, vested immediately.
• Basic life and supplemental life insurance.
• Short-term and long-term disability coverage.
• Accident insurance.
• Pet insurance.
• Corporate-sponsored events.
• Paid professional development and salary incentives through learning and certification opportunities.
• Flexible benefits package.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior