Effective next year, those selling their homes in Thurston County will have to provide a whole-home energy efficiency rating with the sale listing.
The Home Energy Score (HES), a rating from 1 to 10 based on the energy efficiency of a home, is intended as a tool for homebuyers to better understand the annual estimated energy costs of a home.
After roughly six years of development and over 300 public comments split evenly for and against, the Board of Thurston County Commissioners passed an ordinance during its regular business meeting Tuesday, March 17, requiring that a HES be completed and disclosed as part of the real estate listing for subject buildings within Thurston County.
The ordinance goes into effect 365 days after signing.
“What we’re doing today is really starting that implementation period,” said Commissioner Carolina Mejia, adding that workforce development and engagement with community members and stakeholders will continue over the next year.
The ordinance requires the seller to obtain a home energy performance report from a certified private sector assessor prior to putting a property on the market. The assessor goes through the home and determines an HES on a 1 to 10 scale based on over 40 data points, including the home’s age, size, number of stories, foundation, windows, insulation, heating and cooling systems and water heating systems.
The HES is valid for 10 years after the assessment, provided there are no major changes to the home.
The assessment takes about an hour to complete and can cost between $150 and $350.
Low-income households, defined as those eligible for any county or federal low-income assistant programs or those earning 80% or less of the median area income, will either have their assessments paid for by the county or be exempt from the HES requirement, depending on available funding.
Properties on federal or tribal land are also exempt. The policy additionally lays grounds for sellers to obtain an exemption for undue hardship.
“There are protections in place for people who can’t afford this,” said Thurston County Commissioner Emily Clouse.
The assessment does come with a list of suggested cost-effective energy improvements, but the county’s policy does not require sellers to make any energy improvements to the home.
The policy’s goal is to incentivise home energy improvements and to better inform buyers about the energy costs associated with property listings.
The ordinance was primarily opposed by stakeholders within the real estate industry, who said the cost of mandatory HES assessments and the lack of qualified HES assessors in the area would harm the local real estate market and place undue burden on people trying to sell their homes.
“We believe the ordinance still contains several significant implementation questions and technical issues that warrant additional discussion,” said Dawn Baker of the Thurston County Realtors Association.
The association sees the value in a voluntary HES model, Baker said, but asked the county to take more time and amend the policy to be “clear, practical and workable in real estate transactions.”
Some homeowners also opposed the ordinance, saying the assessment fee was an unnecessary expense added onto an already complicated and expensive home selling process, and that the HES requirement would make it harder for older homes to sell.
Climate advocates and energy-conscious homeowners were largely in favor of the ordinance.
“This is a measure that will provide transparency and allow buyers and sellers to communicate about the energy performance of these homes,” said Chris van Dalen, the former executive director of the Northwest EcoBuilding Guild, during public comment at Tuesday’s meeting. Now retired, van Daalen was involved in the creation of the Thurston Climate Mitigation Plan in 2020 and the initial development of the county’s HES policy.
In addition to encouraging energy efficiency in the real estate market, van Daalen said, the HES policy helps address the growing housing affordability crisis by addressing energy costs associated with home ownership.
“We know from research that low income households have a three-times greater energy burden as part of their overall housing budget,” van Daalen said. “And this will help to address inequality, while at the same time helping us keep the commitments for the Thurston Climate Mitigation Plan that we've all put so much time into.”
The HES initiative is one of the climate actions laid out in the Thurston Climate Mitigation Plan, developed by the Thurston Regional Planning Council, Thurston County and the cities of Lacey, Tumwater and Olympia to reduce greenhouse gases in the region.
Thurston County also signed an interlocal agreement with the cities of Lacey, Tumwater and Olympia to further the goals outlined in the Thurston Climate Mitigation Plan.
The City of Olympia reviewed a draft of its HES ordinance on March 11 and is set to vote on the policy on March 24.
The City of Lacey lists the HES ordinance as a “medium priority” on its 2026 work plan. The City of Tumwater reviewed the model ordinance on Feb. 24 and plans to continue discussion this year, with a goal of taking action in 2027.
While nearly 80 cities across the country, including Portland, have already established mandatory HES policies, Thurston County is the first county in the nation to implement a HES requirement.
That gave Commissioner Wayne Fournier enough trepidation to abstain from Tuesday’s vote.
“Being the first is cool, but being the first is dangerous,” Fournier said, pointing to legal concerns he felt had not been adequately addressed by the county’s legal counsel.
Specifically, Fournier said, he is concerned that, unlike cities, counties may not have explicit legal authority to implement a mandatory HES ordinance.
“I can't, in good faith, support a policy that carries unresolved authority questions, potential liability and operational challenges,” Fournier said. “Moving forward without addressing these risks could expose, in my opinion, the county and its elected officials to lawsuits, loss of insurance coverage and operational failure.”
While legal counsel was not present at Tuesday’s commission meeting, Fournier’s fellow board members said they interpreted the legal guidance they’d received from the county’s counsel through the multi-year development of the ordinance differently.
“I think that Wayne and I were at completely different meetings,” said Commissioner Rachel Grant, pointing to her notes from legal counsel that say Thurston County has “implied and expressed authority” to move forward with the HES ordinance.
Commission Chair Tye Menser agreed.
“What I heard was a stronger legal position than I guess what he (Fournier) heard,” Menser said.
Fournier said that, while he supported the goals of the HES ordinance and would not vote against it, he ultimately didn’t have enough trust in its legal standing to vote for it.
“I hope we proceed with caution,” he said.
The ordinance passed with four votes in favor.
For more information on the county’s HES policy, visit https://www.thurstoncountywa.gov/climate/home-energy-score
