Right-sizing your HVAC system starts with accurate calculations and precise design. At Go Green Heating & Air Conditioning, we perform certified Manual J Load Calculations (included free with all new installation quotes) and Manual D ductwork design to make your new furnace, AC, or heat pump perfectly sized and installed for maximum comfort and efficiency.

Why Manual J Load Calculation Matters
Most homeowners don’t realize that HVAC performance begins with math. Manual J Load Calculations (or HVAC load calculations) are the industry-standard method used to size heating and cooling equipment accurately.
It takes into account critical factors in your home, such as:
- Square footage and layout
- Ceiling heights and insulation levels
- Window size, type, and orientation
- Local Denver climate data
- Number of occupants and internal heat gains
Many contractors skip this step, often guessing based on square footage or simply replacing equipment with the same size you currently have. Systems sized this way are frequently 25% to 100% oversized, which can lead to:
- Hot and cold spots throughout your home
- Higher utility bills from wasted energy
- Excess wear-and-tear on your system
- Shorter equipment life
These calculations are the foundation for ductwork design (Manual D), assuring airflow is balanced, temperatures are consistent, and every room stays comfortable.
Certified HVAC Load Calculations & Duct System Design
Backed by NATE certification, our team uses Manual J Load Calculations along with proper ductwork design (Manual D) to guarantee your system is:
- Correctly Sized: Matching heat gain and heat loss to your home’s unique structure.
- Correctly Installed: Optimizing energy usage and lowering annual bills.
- Comfort-Oriented: Guaranteeing airflow, humidity, and temperature remain consistent across every room.
- Future-Proof: Providing the right foundation for duct modifications, system upgrades, or hybrid heat pump solutions in the future.

Features & Benefits of Load Calculations with Go Green
Free Manual J Load Calculation
Included with all new installation quotes.
Precision Installation
We use room-by-room measurements and airflow requirements, not “rule of thumb” sizing.
Energy Savings
Lower monthly bills thanks to right-sized equipment.
Healthy Airflow
Proper duct sizing and layout optimization keep every corner of your home comfortable.
Trusted Expertise
BBB A+ rating, Gold Star award, and decades of experience.

Why Homeowners in Arvada Trust Go Green
- Honest Quotes – No gimmicks, no hidden fees.
- Certified Expertise – NATE-certified technicians and trained installers.
- Guaranteed Workmanship – 100% satisfaction guarantee
- Local Roots – We’re based in Arvada and know the climate well.
Get Started Today
Our NATE-certified technicians use ACCA-approved methods to deliver the right system and the right airflow. Contact us today to request your free estimate.

Other Areas We Serve
We perform Manual J Load Calculations and HVAC duct design services across Arvada and surrounding communities, including:
