G&J HVAC Design — Manual J & D Design (DMV)
G&J HVAC Design

DMV HVAC DESIGN • RESIDENTIAL

Premium Manual J & Manual D Design for Maryland, DC & Virginia

With 14+ years of residential HVAC design experience across the DMV, we deliver precise load calculations and duct designs tailored to county requirements. We also offer permit expediting to smooth approvals in Fairfax, Arlington, Prince William, and beyond.

Design Intelligence
14+ years driving precise HVAC design. Permit expediting available.

14+ Years of Residential HVAC Design in the DMV

We’ve designed projects across Maryland, DC, and Virginia, including work in Fairfax, Arlington, and Prince William counties. Our team has completed Wrightsoft training and ACCA programs to ensure compliant, efficient solutions.

  • 14+ years of hands-on Manual J load calculation and duct design experience
  • Wrightsoft certified designer
  • ACCA trained for industry-best practices
  • Permit expediting to simplify county submissions

We’ve served clients across the DMV and beyond, with a emphasis on Fairfax, Arlington, and Prince William counties.

Wrightsoft and ACCA training certificate HVAC designer at a desk reviewing plans

Credentials & Focus

Our designer is trained through Wrightsoft and ACCA programs, ensuring rigorous standards for load calculations and duct design, while staying mindful of county-specific compliance.

Pricing

Clear, Transparent Pricing

Low upfront investment for high-precision HVAC design. Prices shown are per system.

Manual J + D

$400 / per system
  • Comprehensive load calculation
  • Duct design coordination
  • System optimization for comfort & efficiency
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Manual J Only

$300 / per system
  • Accurate load calculation for HVAC sizing
  • Ideal for simple projects or where duct design is handled separately
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Expedited Permit Service

Fast-track

Fast-track county submissions to reduce wait times. Pricing varies by project scope; contact for details.

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Process

Three-Step Turnaround

Clear, collaborative, and efficient. From first consult to permit submission, we streamline your project.

Consultation

We gather home details, goals, and constraints to tailor the design scope.

Design

Accurate Manual J load calculations with duct design to optimize performance.

Permitting

Prepare and submit documents for permit approvals with county support as needed.

Regions We Serve

We offer Manual J and Manual D design services across Maryland, Washington DC, and Virginia. Our primary focus includes Fairfax, Arlington, and Prince William counties, with permit expediting to simplify county processes.

  • Maryland: Montgomery, Prince George’s, Howard, Anne Arundel
  • District of Columbia: DC proper and surrounding suburbs
  • Virginia: Fairfax, Arlington, Prince William, Loudoun, Stafford
Permit Expediting

We handle county submissions on your behalf to minimize back-and-forth and accelerate approvals.

Get in Touch

We respond within 24 hours in most cases.

Alternatively, you can email us with your information and we will call you within 24 hours. For immediate details, visit gjhvacdesignllc.com to find our phone number.

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