When you’re looking to buy or sell a home, there’s more to consider than just square footage or curb appeal. One of the most important—and often overlooked—factors is how efficiently a home uses energy. That’s where the Home Energy Score (HES) comes in.
Developed by the Oregon Department of Energy, under the guidance of the U.S. Department of Energy (USDOE), the Home Energy Score provides a simple, standardized way to measure a home’s energy efficiency. Think of it like a miles-per-gallon rating for houses—it helps buyers and sellers understand how much energy a home uses.
The HES report provides the score and makes specific recommendations where a homeowner could improve. These suggested improvements are prioritized by cost efficiency. While all homes could benefit from solar panels, they are expensive and may take many years to break even on the investment. Your money is probably better spent on HVAC efficiency and insulation, which are less expensive with a quicker payback.
Where It’s Required
In Oregon, the Home Energy Score requirement currently applies to homes listed for sale in cities of Portland, Hillsboro, and Milwaukie. Other cities—including Eugene, Corvallis, Salem, and Gresham—are actively considering adopting the program in the future.
Right now, the rule focuses on single-family detached homes, but revisions are being discussed to include stacked condominiums and manufactured homes as well.
How the Home Energy Score Works
The Home Energy Score is an asset-based evaluation, meaning it evaluates the physical features of the property itself—not the occupant’s habits or energy use.
Certified assessors inspect elements like:
Heating and cooling (HVAC) efficiency
Properly sealed ducts
Insulation levels in walls, attics, and floors
The result is a score on a scale from 1 to 10, where 10 represents the highest energy efficiency. A score of 1 doesn’t mean the home is “bad,” but it does indicate room for improvement in terms of energy use and cost savings and the owners energy costs will be higher.
In the Portland Metro area, the average Home Energy Score is around 4.6. However, after completing the energy-saving recommendations outlined in the report—such as sealing air leaks, upgrading insulation, or improving heating and cooling systems—the average score rises to 7.1.
Importantly, there is no minimum required score for homes to be listed or sold. The goal is simply to provide transparency and encourage improvements over time.
Why It Matters
For sellers, the Home Energy Score can be an opportunity to highlight your home’s strengths and demonstrate proactive care for energy efficiency. For buyers, it offers a clear comparison point between properties and can help estimate future utility costs.
In short, the Home Energy Score benefits everyone by bringing energy performance into the conversation—something that’s good for your wallet and the planet alike.