What is a Home Energy Score?

A Home Energy Score (HES) is a tool that helps home owners understand the annual estimated energy costs of a home. The HES provides a whole-home efficiency rating from 1 to 10. It’s like a vehicle miles-per-gallon rating.

HES assessment overview

An assessment is conducted by a certified assessor, takes about one hour to complete, and typically costs $150-350. An assessment covers 40+ data points from a home including:

• Age
• Size
• Number of stories
• Foundation
• Windows
• Insulation
• Heating and cooling systems
• Water heating systems

HES score and recommendations

An assessment provides an energy use score and list of cost-effective energy efficiency improvements. Priority improvements are estimated to pay back in ten years or less.

Draft regional HES policy

The Thurston Climate Mitigation Collaborative drafted a regional model ordinance for HES.

Where HES stands now in Tumwater

The City does not currently require Home Energy Scores for buildings in the City. The City of Tumwater is reviewing information related to the regional model ordinance and continues to consider the advantages and disadvantages of options for and against Home Energy Score policies for the City. The topic remains an item of discussion and ongoing City and Council research.

City Council Work Session February 24, 2026

City Council Work Session Presentation

For more information, contact Alyssa Jones Wood at AJonesWood@ci.tumwater.wa.us.