Seattle Energy Code

The Seattle Energy Code is a construction code that ensures new buildings are efficient from the start. Every three years, the City of Seattle updates the energy codes that govern non-residential commercial and taller multifamily buildings to make them even more effective and move us toward a clean energy future. In 2021, updates and amendments were signed into law to make Seattle's 2018 commercial energy code one of the strongest on climate in the nation. 

Why Energy Codes Matter

Greenhouse gas emissions from Seattle's buildings continue to increase in large part due to the growth in new construction heated by dirty fossil fuels such as fracked gas. Pollution from fossil fuels degrades the air we breathe both indoors and out, especially for children, seniors, and BIPOC communities. Robust energy codes governing new non-residential commercial and taller multifamily buildings (four or more stories) will protect our health and move us into a clean energy future.  

Commercial and multifamily buildings are built to last. If we continue building with gas, we are essentially "locked in" to dirty fossil fuels in these buildings for decades. Getting it right the first time is the most economical path to a clean energy future. 

Energy Code Updates

Seattle's commercial energy code governs how new non-residential commercial and taller multifamily buildings (four or more stories) use energy. The code also applies when these buildings are undergoing major renovations, or when space and water heating systems are being replaced. The Seattle Department of Construction and Inspections (SDCI) is responsible for managing amendments to the energy codes. Key updates in the 2018 code (adopted in 2021) include: 

  • Eliminating fossil fuels like gas and electric resistance from most water heating and space heating systems in new construction and substantial alterations, and in most equipment replacements for:
    • Space heating: Updated code applies to commercial and multifamily (effective March 2021).
    • Water heating: Updated code applies to hotel and multifamily (effective January 2022) and to new construction and substantial alteration non-residential commercial buildings (effective April 1, 2022).
  • Improving building exteriors to improve energy efficiency and comfort.
  • Creating more opportunities for solar power.  


The benefits for building owners and tenants are higher performing buildings and lower utility costs. These codes will also drive innovation that leads to new, green jobs and eliminates key sources of climate pollution. Electrified buildings keep residents and tenants safe from gas line leaks and explosions, as well as eliminating pollution and environmental hazards that occur at the drill site and during transportation of fossil fuels. Given the urgency of avoiding the most catastrophic impacts of climate change, any new buildings constructed with fossil fuels will need to commit financial resources to removing those fossil fuel uses within the next 25 years.

The updated energy code eliminates most direct carbon emissions from new and renovated buildings, which is our most economical opportunity to transition to clean electricity. Marginally increased construction costs will be repaid through reduced utility bills, and any additional upfront costs will decrease as industry adapts. 

By strengthening our energy codes today, we're ensuring our buildings are efficient from the start and investing in a healthier tomorrow.

More Information

Sustainability and Environment

Jessyn Farrell, Director
Address: 700 5th Avenue, #1868, Seattle, WA, 98104
Mailing Address: PO Box 94729, Seattle, WA, 98124-4729
Phone: (206) 256-5158

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