Boulder planning board backs 2024 Wildland Urban Interface code updates, expands WUI map

The City of Boulder Planning Board voted to recommend that City Council adopt Ordinance 86‑95 to adopt by reference the 2024 edition of the International Wildland‑Urban Interface Code and to update the city’s Wildland‑Urban Interface (WUI) map.

The ordinance and map update were the core of a 30‑minute staff presentation and an extended question-and-answer period during the April 15 meeting. Lisa Hood, principal planner with Planning and Development Services, opened the staff presentation and framed the item: “The purpose tonight is for Planning Board to make a recommendation to the city council on ordinance 86 95.” Chief David Lowery of Boulder Fire Rescue and Rob Adrians, the city’s chief building official, joined Hood for technical detail and answered board questions.

Why it matters: the changes update technical building‑code measures for homes and structures in areas where developed neighborhoods meet vegetated open spaces, and they expand the geographic area where those measures apply. Board members spent much of the meeting questioning how the expanded map and new local amendments would affect multifamily and higher‑density parcels, the amount of private green space available on small lots, and how the city will pair code changes with outreach, incentives and enforcement.

Most of the proposed local amendments target vegetation management and “defensible space” rather than structural house‑hardening. Hood and Chief Lowery explained the split: chapter 5 of the WUI code covers ignition‑resistant construction while chapter 6 governs fuel modification and defensible space. Lowery described the emphasis on vegetation: “When we really start talking and I start rattling off these proposed amendments to you guys ... it’s really all focused on that chapter 5 and chapter 6 as we move forward here.” Staff said many of the additions are intended to align Boulder’s rules with a pending state wildfire‑resiliency map and to incorporate ember‑cast modeling that showed potential ignition risk farther into the city than the current map covers.

Key local amendments described by staff include: - Adding a defined 0‑to‑5‑foot “noncombustible zone” around new buildings in the WUI where no combustible vegetation or materials would be allowed (applies to new construction, not retroactive); - Requiring ignition‑resistant surface materials for new decks and added screening or enclosure of combustible under‑deck space for elevated decks; - Requiring noncombustible materials for new fencing or gate sections within about 8 feet of a structure (new construction or replaced fences); - Prohibiting planting of juniper species in the WUI and requiring use of low‑flammability plants in the 5‑to‑30‑foot zone for new landscaping; and - Clarifying that much of enforcement and technical design (emergency access, water supply) remains controlled by Boulder’s existing design and construction standards (DCS) rather than the WUI code.

On the map expansion, staff said the proposed WUI boundary would grow significantly: “When we add this new particular map, it does it right, pretty close to 1,600 parcels. That's quite a jump…98% of that is all that ignition resistant 3,” Chief Lowery said, noting that the added area is largely the lower‑stringency category where the city expects vegetation management rules rather than extensive home‑hardening requirements.

Board members pressed staff on a variety of practical and equity concerns: how the code would affect multifamily and mobile‑home parks, whether plant lists would be ready before the ordinance takes effect, potential insurance impacts, and how the city would enforce maintenance requirements. Staff repeatedly emphasized that the building‑code changes are intended for new construction and for components replaced as part of permitted work; they said retrofit or broad retroactive requirements are not part of this ordinance. Lisa Hood said outreach will include a mailer to properties in the proposed WUI area and public office hours; the city’s “detailed home assessment” and grant programs were highlighted as non‑regulatory tools to help property owners adapt.

Votes and outcome: Planning Board moved and passed the primary recommendation by roll call. The board’s recommendation to adopt Ordinance 86‑95 and to update the WUI map passed on a 6–1 vote (one member opposed). After that motion passed, the board approved a second, separate motion asking City Council to direct staff to research methods to protect vegetation and green space for multi‑unit housing, higher‑density zones, and small‑lot properties; that motion also passed by a 6–1 vote.

Quotes from officials: “‘The WUI is the Wildland Urban Interface,’” Hood said while explaining the geographic scope of the code. “‘It’s an important subject,’” Chief Lowery told the board as he introduced technical changes.

What happens next: staff said the same ordinance will go to Boulder City Council for first reading the week following the Planning Board meeting; a second reading (and the public hearing before council) is scheduled roughly a month later. Staff also said additional land‑use code and landscaping changes will follow later in the year to align water‑wise landscaping and other programs with the WUI rules.

Ending note: staff emphasized the ordinance is one part of a broad wildfire‑adaptation strategy that includes education, incentives, operations and planning. Hood said the WUI building‑code changes are intended to be paired with outreach and grant programs that help property owners implement the measures voluntarily where possible.