The Department of Energy’s Home Energy Score (HES) has been around since 2012, but Washington State jurisdictions have recently discovered that requiring a HES on existing home sales could be a useful tool to fulfill their climate pollution reduction goals. On the other hand, doing so may also create additional costs, implementation challenges, and unintended consequences for homeowners and the housing market.
The backstory and key players:
- In 2012, DOE officially launched the “Home Energy Score” (HES) as a standardized one-to-ten rating system for homeowners, buyers, and renters to understand a home’s efficiency. To do so a DOE trained HES Assessor completes a home inspection/evaluation so they may provide potential energy saving recommendations to the owner as well as the home’s unique HES score with a ten rating being the most efficient.
- Biden-Harris Administration’s Inflation Reduction Act (IRA) of 2022 had 3 main pillars of legislation which included significant investments into the nation’s clean energy and emission-reduction technologies to put the nation on track for a goal of net-zero emission by 2050.
- The Climate Pollution Reduction Grant (CPRG) is a federal funding program through the US Environmental Protection Agency (EPA), that provides funding to states, local governments, tribes, and territories to develop and implement plans for reducing greenhouse gas emissions and air pollution.
- Washington State received a $3 million CPRG to identify and implement a Comprehensive Climate Action Plan (CCAP) to meet WA State’s emission reduction targets outlined in RCW 70A.05 and RCW 70A.45.
- In Washington, the WA Climate Partnership, led by WA State Depts of Commerce and Ecology, backboned the effort to develop the Comprehensive Climate Action Plan (CCAP) as a step in being compliant with the CPRG requirements.
- In 2020 Thurston County along with the cities of Lacey, Olympia and Tumwater joined the Thurston Regional Planning Council to create the Thurston Climate Mitigation plan with goals of reducing regional emissions 45% below 2015 levels by 2030 and 85% below 2015 levels by 2050.
- In March of 2026, after 6 years of collaboration between the regional authorities, Thurston County, WA became the first county in the nation to mandate home sellers obtain a home energy score (HES) prior to listing a property for sale. It is explicitly identified as a priority action in our adopted Climate Mitigation Plan” stated Thurston County Commissioner Carolina Mejia. Effective 2027, the proposed plan is to require a home seller obtain a HES score prior to listing. Exceptions apply to certain types of dwellings and those listed for sale by owner.
- Mandated HES on homes sales and the program’s implementation and governance in Thurston County is a fluid discussion between real estate housing professionals and jurisdictional representatives. Currently, the HES is considered informational only and requires the score to be available to potential buyers. The exact method of notification to a buyer has not been finalized and the home seller is not required to complete the HES assessors suggested efficiency improvements.
Concerns that have been raised by Real Estate Housing Professionals include:
- Why add costs to a seller for the HES audit when it could be a part of the buyer’s home inspection?
- Will the results of the HES impact the value of the home by lenders and appraisers?
- Will future policy changes eventually tie HES results to additional regulatory requirements, including costly home improvements?
- Fears that HES will negatively contribute to the region’s home affordability crisis.
- Construction guidelines and practices have evolved significantly over the years, could or should a 50+ yr old home be expected to achieve the same HES as a home built in more recent years.
- Questions remain regarding how compliance and enforcement would function in practice.
- Limited availability of certified assessors may create implementation challenges in some markets.
What you should know as a Real Estate Housing Professional:
- Home seller required HES in Thurston County is a topic that many jurisdictions across Washington State are following closely. With a directive to reduce greenhouse gas emissions and air pollutants, jurisdictions are exploring HES programs as one potential tool to support their climate planning goals.
- House Bill 1015, regarding energy labeling of residential buildings, first read in the 2025 regular session, failed to advance but was then reintroduced again in 2026. Given ongoing legislative interest in residential energy labeling, industry professionals expect similar proposals to continue surfacing in future sessions.
- You can find Washington’s RCWs, WACs and other current legislation at aap.leg.wa.gov.
- Does your County/Jurisdiction have a current Climate Mitigation Plan and how it could impact your housing market?
- Ask your home inspector if they are planning on getting certified to provide HES.
- If you have a REALTOR® association near you, ask them where they stand on the topic.
How HES is utilized in the future remains to be seen but it is important that real estate housing professionals are a part of the ongoing conversation.
