Your Help Needed to Repair the Wildland-Urban Interface Code
Charlotte Persons
Readers of The Echo will be overjoyed to hear that NOT ONE, BUT TWO SOLUTIONS have been proposed to correct problems caused by including defensible space requirements in the 2021 Wildland-Urban Interface Code. Unfortunately, both remain in doubt.
You can help by registering your support for ESB 6120.
In 2018 the state legislature passed Senator Van De Wege’s bill to enforce parts of the Wildland-Urban Interface sections of the International Building Code. This law requires using ignition-resistant building materials and methods for residences within Wildland-Urban Interface areas.
However, the Washington State Building Code Council (SBCC) went beyond this law and included defensible space requirements within the 2021 WUI Code Amendments. These would have resulted in the removal of thousands of trees across 70% of the state!
For more about this code’s requirements, see the “Background” section at the end of this article.
Problems with the 2021 WUI Code Amendments spurred environmental organizations, associations of cities, counties, and builders, and state agencies like the Department of Fish and Wildlife and the Department of Commerce to write letters, testify publicly, and lobby elected representatives and the SBCC. After many months of work, the two possible solutions discussed in this article emerged.
Best solution – Pass Senate Bill 6120
In January 2024 Senator Van De Wege filed SB 6120 for this Washington State legislative session. This bill reinforces the language of his original bill passed in 2018. It requires property owners to use ignition-resistant materials and methods for new and existing residences within the Wildland-Urban Interface (WUI). It specifically excludes the “defensible space” parts of the International Building Code.
The bill also directs the Washington Department of Natural Resources to create two separate maps—a statewide map of wildfire hazard and wildfire risk maps at the county level. Local jurisdictions can create their own maps using WA DNR methods. Only homes in the two highest categories of wildfire hazard are required to follow the WUI codes. For existing homes, local jurisdictions can choose to remove WUI code requirements for exterior construction projects.
This bill addresses most of the problems caused by the 2021 WUI Code Amendments, and Black Hills Audubon Society wholeheartedly supports it.
However, as of February 28 it is not clear whether ESB 6120 will pass during this legislative session. The bill has cleared the Senate and is now in the House, but four more steps must be completed before March 9 if the bill is to pass this session.
How you can help: Comment favorably on ESB 6120 by going to https://app.leg.wa.gov/billsummary?BillNumber=6120&Year=2023&Initiative=false
In the upper right corner by the bill description, click on “Send a comment on this bill to your legislators”.
Another solution – Proposed amendments to the WUI Code
The State Building Code Council (SBCC) in its November 18, 2023 meeting proposed language to amend the 2021 WUI Code Amendments. This language reduces tree removal requirements for homes within the WUI areas to ten feet from homes, outbuildings, and overhead wires.
This version is not perfect and does not address the problems of the WUI map created by WA Department of Natural Resources. Nevertheless, Black Hills Audubon Society and other environmental groups supported the new language in the February 9 public hearing.
If ESB 6120 does not pass the legislature this session, BHAS hopes that SBCC will pass the proposed language to amend the 2021 WUI Code Amendments. The SBCC will probably vote on the proposed language at their next meeting on March 15, the date that the code is to go into effect.
Background on WUI Codes in Washington State
The growing number of wildfires that have burned homes and communities across the Western states spurred interest in adopting the Wildland-Urban Interface sections of the International Building Code. The Washington state legislature joined this movement in 2018 by passing ESB 6109, sponsored by Senator Van De Wege.
The law required that new homes, and existing homes with new exterior construction, follow parts of the International Building Code. These parts require that property owners “harden” residences and outbuildings against wildfire by using ignition-resistant building materials and methods. RCW 19.27.560, passed in 2020, had the same requirements.
However, environmental organizations across the state were caught flat-footed when in April 2023 the Washington State Building Code Council (SBCC) published the 2021 WUI Code Amendments. We were surprised because this code went beyond the legislation by including the defensible space requirements of the International Building Code.
Anti-science Defensible Space Requirements
The ostensible purpose of defensible space is to slow down ignition of houses until the wildfire fighting forces can arrive to “defend” the home. The defensible space required by the International Building Code varies between 30, 50 and 100 feet around buildings, depending on the slope of the land, access to water, and so on. Within defensible spaces, tree canopies can be no closer than 10 feet to a building, another tree, or overhead wires.
Long story short, defensible space requirements in the 2021 WUI Code Amendments would force the removal of thousands of trees. This puts the defensible space requirements in direct conflict with at least seven state laws and regulations, such as Shoreline Management and critical areas protections—and local jurisdictions’ tree codes and climate mitigation plans.
Counter-intuitively, recent wildfire science studies conclude that tree removal around homes does not actually protect them. “Home hardening” with fire resistant materials is much more effective.
Problems with the Map Designating WUI Areas
In July 2023 the Washington Department of Natural Resources (DNR) published the map of wildland-urban interface areas for the 2021 WUI Code Amendments. The map’s definition is only down to 3 miles, so it is often difficult to decide whether a specific land parcel is within a designated WUI area.
Worse, the map is based on proximity to cities and population density instead of wildfire risk. Against all accepted wildfire science, all dense vegetation, from farmers’ fields to forests, is considered as presenting the same amount of wildfire risk. The DNR criteria mean that urban and rural land areas with no history of wildfire and no proximity to high wildfire fuel loads (forests) are designated as WUI areas. Home owners living in these WUI areas would be unnecessarily burdened with complying with the WUI code.
Even worse from the environmentalists’ point of view, this method of designating WUI areas multiplies the amount of required tree removal in defensible spaces because 70% of the state, and most of Western Washington, is within the designated WUI areas.
Photo credit: Trees, Homes, and Mt. Rainier, by Rachel Hudson.
