Building Code Information

International Residential Code (IRC) significant changes & International Wildland-Urban Interface (WUI) information:

2021 IRC Significant Changes

WUI Code Summary

WUI Code Roofing

WUI Code Exterior

WUI Code Deck

The State Building Code Council has adopted the 2021 editions of the codes below, with amendments. These codes went into effect March 15, 2024.

Which Codes are in Effect?

2021 International Building Code – WAC 51-50

2021 International Residential Code – WAC 51-51

2021 International Mechanical Code – WAC 51-52

2017 NFPA 54, National Fuel Gas Code – WAC 51-52-21000

2021 Edition of NFPA 58, Liquefied Petroleum Gas Code – WAC 51-52

2021 International Fuel Gas Code - WAC 51-52

2021 International Fire Code – WAC 51-54

2021 Uniform Plumbing Code & Standards – WAC 51–56 and WAC 51-57

2021 Washington State Energy Code – (International Energy Conservation Code) - WAC 51-11

2021 International Existing Building Code-WAC 51-50

Design Requirements
Design Wind Speed: 110 mph (Exposure B or C depending on location)
Ground Snow Load:  25 psf (Uniform, non-reducible)
Snowdrift:  25 psf ground snow loads shall be considered
Seismic Zone:  D, E
Rainfall:  2 inches/hour for roof drainage design
Frost Line Depth:  18 inches


Where can I view/purchase these codes?

A variety of sources to purchase these codes are available online. They are also available for purchase directly through the Washington Association of Building Officials bookstore. Copies of the codes are always available for viewing at City Hall. Also, many libraries keep copies of current "standard codes" (though they may not include local amendments).


Washington State amendments can be downloaded for free on the Washington State Building Code Council's website. State amendments are also available for purchase in hard copy through the WABO bookstore.