2021 Seattle Code Adoption - What & Why

The effective date for the 2021 Seattle codes will be November 15, 2024. Until then, applicants may use either the 2018 or draft 2021 Seattle codes. The 2021 Seattle codes adoption ordinance is continuing through the final stages of the approval process. Printed copies of the Seattle codes and complete digital versions will be available after the November 15 implementation date.

What’s Happening Now?

Seattle is proposing to adopt a suite of construction codes that include National, State, and Seattle amendments. The significant changes summary, below, outlines what will be included in the 2021 Seattle Codes.

• 2021 Seattle Code Significant Changes Summary
• 2024 Seattle Boiler and Pressure Vessel Code
• Amendments to 2021 International Fire Code
• Amendments to 2021 International Building Code
• Amendments to 2023 National Electrical Code
• Amendments to 2021 Washington State Energy Code
• Amendments to 2021 International Existing Building Code
• Amendments to 2021 International Fuel Gas Code
• Amendments to 2021 International Mechanical Code
• Amendments to Chapter 51-56 WAC
• Amendments to 2021 International Residential Code

We also have a brief guide to understanding the markings in the draft code change  documents to help you understand the proposed changes.

The State of Washington Building Code Council has posted the changes for the 2021 codes at the following links:

• Washington State Building and Existing Building Codes, Chapter 51-50 WAC
• Washington State Residential Code, Chapter 51-51 WAC
• Washington State Mechanical and Fuel Gas Codes, Chapter 51-52 WAC
• Washington State Fire Code, Chapter 51-54A WAC
• Washington State Energy Code, Energy Code SBCC
• Washington State Wildland Urban Interface Code, Chapter 51-55 WAC
• Washington State Plumbing Code, Chapter 51-56 WAC 

The City of Seattle adopts most of these changes. SDCI will post the proposed 2021 Seattle code changes once they are available.

Current Seattle Codes Are Available

The 2018 Seattle construction codes are available for purchase through the International Code Council as a bookmarked pdf copy that you can download. 

You can order printed copies of the Seattle construction codes and errata through SDCI. View our publication list for prices. To order, please submit a request through the Seattle Services Portal using the Permits - Trade, Construction and Land Use option. See How to Purchase Seattle Code Books From SDCI for instructions on how to submit your request.

Read only versions of the Seattle construction codes and errata are available on the code webpages.

Project Benefits

Regular updates to Seattle's construction codes make it easier to:

• Incorporate emerging technology and materials into construction to increase a building's safety, usability, and lifespan

• Keep Seattle competitive and innovative with early adoption of national code changes

• Adopt requirements that ensure Seattle's leading-edge energy and carbon reduction goals are met

• Decrease differences in construction code adoption and enforcement with neighboring communities     

The End Result

SDCI is preparing for the adoption of the 2021 editions of the national model codes published with State of Washington and local Seattle amendments.