Builders, homeowners, and developers often confuse HERS ratings with ENERGY STAR. They are related but they are not the same thing. This page explains the difference and when you need each.
A HERS Index is a number. It ranges from 0 to 100+. Lower means more efficient.
ENERGY STAR is a certification. It is the recognition that a home meets a specific performance program.
A home has a HERS Index. A home either meets ENERGY STAR or it does not.
The Home Energy Rating System (HERS) is a scoring system developed by RESNET (Residential Energy Services Network) in 1995. The score is based on a standard methodology that uses the home’s plans, construction, and a series of on-site inspections.
A typical resale home scores around 130. A new code-built home (the bare minimum allowed by current energy code) scores around 100. An ENERGY STAR-certified home scores in the mid-50s to mid-80s depending on climate zone. A Zero Energy Ready Home might score in the 40s. A net-zero home scores 0 or below (a HERS Index of -5 means the home produces 5% more energy than it consumes over the year).
The full HERS rating process involves:
The HERS Index is registered in the national RESNET registry. A HERS certificate is a legal document recognized by HUD, the IRS, most lenders, and many state and utility programs.
ENERGY STAR is a government-backed certification program run jointly by the U.S. EPA and U.S. DOE. To earn the ENERGY STAR, a home must meet a long list of prescriptive and performance requirements:
The ENERGY STAR program issues a separate certificate (the “ENERGY STAR label”) after the home passes inspection. The label is what buyers can find in the program’s registry.
If you are a builder claiming 45L tax credit, you need ENERGY STAR (or DOE ZERH). The HERS Index is part of the documentation, but the ENERGY STAR label is what the IRS requires.
If you are a homeowner refinancing with an Energy Efficient Mortgage (EEM), lenders typically accept a HERS Index alone. You may not need ENERGY STAR unless your lender specifies it.
If you are a state utility program, most accept either ENERGY STAR or an equivalent HERS score. Verify with your utility.
If you are just curious about how your home performs, a HERS Index alone is sufficient.
| Factor | HERS Score | ENERGY STAR |
|---|---|---|
| Blower door test | Required (factor) | Required (target) |
| Duct leakage | Required (factor) | Required (target) |
| Window U-factor and SHGC | Factor | Prescriptive or target |
| HVAC SEER/HSPF | Factor | Prescriptive or target |
| Insulation R-value | Factor | Prescriptive or target |
| Final HERS Index | OUTPUT | Below target required |
| Water management | Not scored | Required |
| Combustion analysis | Not scored | Required |
| Heat pump sizing validation | Factor | Required |
HECS USA is a RESNET-accredited HERS Rating Provider and an ENERGY STAR Certified Homes Verifier. Our 45L workflow combines both:
One visit. One report. One phone number: (859) 983-7382.
Yes — DOE Zero Energy Ready Home (ZERH) qualifies too. But a HERS Index alone does not satisfy 45L. You need either ENERGY STAR or ZERH.
No — those loans accept any code-built home. ENERGY STAR is not mandatory for government-insured loans. But an EEM (Energy Efficient Mortgage) offers better rates for ENERGY STAR or low-HERS homes.
A pre-drywall inspection typically takes 1.5–2 hours. A final inspection typically takes 3–4 hours including blower door, duct leakage, combustion, and HVAC startup.
HECS USA provides HERS ratings, ENERGY STAR certification, DOE ZERH verification, and 45L documentation across Kentucky, Indiana, Ohio, Tennessee, Illinois, and Missouri. Call (859) 983-7382 or request a quote online.