07 Wildland-Urban Interface Code Staff Presentation — original pdf

Backup

AUSTIN FIRE DEPARTMENT 2024 International Wildland Urban Interface Code Adoption Coordinate and Clarify Goals: Clarify previously adopted local amendments with changing technology and published code. Adjust requirements based on challenges and successes of initial implementation of the International Wildland-Urban Interface Code (WUI). Reasons for amendments: 1. To support operating procedures for Wildfire Operations. 2. Formalize WUI Proximity Zones to clarify structure hardening requirements. 3. Align requirements with current wildfire research. 4. Clarification purposes and formalizing 2015 WUIC interpretations. 2 2024 WUI Highlights Clarifications • Formalize allowances and interpretations • Increased use of the Fire Protection Criteria Manual • Added reference alignment to the Fire Code • Extreme Hazard Condition clarified • Fire Hazard Severity Form (amended) required for • Development under City of Austin Homes Options for Mobility and Equity initiatives • Where a single fire apparatus access road serves more than 30 dwelling units • Wildland definition clarified • Compliance with roof fire-rating • No wood or green roof coverings • Raised-deck systems to comply with International Building Code (IBC) • Exterior ceilings, same treatment as soffits • Artificial turf requirements provided 3 2024 WUI Highlights Changes • Unofficial “Proximity Classes” defined and renamed Proximity Zones A, B, and C • Zone A & B modified protection of accessory structures • Zone B enhanced protection of walls • Zone C enhanced eave and ceiling protection • Zone C reduced roofing, underfloor enclosure, and slope requirements • NEW Ember Ignition Zone • Expiration of initial code launch leniency • Reduced full roof replacement requirement • Reduced boat dock requirements • Driveways, 202 Definitions, 403.2, 403.2.3 • Required for Residential* buildings >150’ from fire apparatus access road where a new fire lane is not otherwise provided • Group Residential* buildings >200’ from fire apparatus access road require a new fire lane or may provide a driveway and automatic fire sprinklers • Serve up to three buildings and three dwelling units max, otherwise a Fire Lane is required *Residential buildings defined as R-3 occupancy in the IBC/IFC 4 Post-Engagement Update 2024 WUI Map Proximity Zones: Zone A: Within 50’ of 40 acre+ wildland Zone B: Within 150’ of 40 acre+ wildland Zone C: • Within 1.5 miles of 750 acre+ wildland • Within 0.5 miles of 40 acre+ wildland (new) Legend: Green/Dark Blue = Wildland & Proximity Zones A & B Light Blue = Proximity Zone C New map shows “offsets” or “buffer zones” from wildland to show more clearly where Proximity zones end. *Note: Map is a visual draft, additional cleanup will be conducted. 5 Austin-Travis County Wildfire Risk WUI Map - Overlay on Wildfire Risk Map 6 Map Data Parcels Area (acres) Austin Full & Limited Purpose 232,340 parcels 212,940acres Current 2015 WUI Map Proposed 2024 WUI Map Parcels % Austin Area % Austin Parcels % Austin Area % Austin 64,349 acres 64,349 acres 21,912 acres 30% 30% 10% 71,040 acres 71,040 acres 55,944 acres 33% 33% 26% Total Contributing Wildland 40 acres or greater * 750 acres or greater Proximity Zone A & B (aka Proximity Zone, Class A &B) Inclusive of wildland Proximity Zone C (currently Ember Zone, Class C) WUI Area 79,263 parcels 34% 80,365 acres 38% 165,706 parcels 71% 109,342 acres 51% 23,790 parcels 10% 60,960 acres 29% 27,067 parcels 12% 86,719 acres 41% 55,473 parcels 24% 19,405 acres 9% 141,526 parcels 61% 93,663 acres 44% *Wildland 40 acres or greater is inclusive of wildland 750 acres or greater. 7 Ember Ignition Zone (EIZ) Section 603.2.1 Research from the National Fire Protection Association (NFPA) and Insurance Institute for Business & Home Safety (IBHS) show • 5 feet around a structure has greatest impact • Noncombustible zone can protect a building from ignition due to • direct flame • radiant heat • wind-blown embers collecting at the base of an exterior wall or structure https://www.nfpa.org/education-and-research/wildfire/preparing-homes-for-wildfire https://ibhs.org/wildfire/near-building-noncombustible-zone/ 8 Ember Ignition Zone (EIZ) Section 603.2.1 The Ember Ignition Zone (EIZ) requires a 5-foot wide, noncombustible area to surround all structures and appendages. The EIZ surface is gravel, pavers, or other non-combustible materials and maintained free of all combustible materials at all times. Artificial turf may not be used in the EIZ, and if used within any defensible space area must have Class A rating per ASTM E108*. Exceptions: • Protected and Heritage trees are allowed to remain in all existing conditions. • • New construction should aim to maintain appropriate distance from such trees. Protective mulch for critical root zone (CRZ) is allowable during construction and shall be removed at the completion of construction. • • For structures of fire resistive and hardened construction**, the EIZ shall only be required 10 feet to each side of required egress points of the structure. Proximity Zone C to allow green, moist, closely mowed lawn grass, dormant grass shall be overseeded with perennial Rye. *ASTM is the American Society for Testing and Materials ** Categorized as Type I and Type II building construction type under the IBC 9 Proximity Zone A Section 504 Proximity Zone B Section 505 Proximity Zone C Section 506 Roof & Accessories Roof & Accessories Skylights Protection of Eaves Skylights Protection of Eaves REDUCED Roof & Accessories REDUCED sloped roof underlayment Skylights Protection of Eaves REDUCED eaves & rafter tails Gutters & Downspouts Gutters & Downspouts Gutters & Downspouts Appendages & structures Appendages & structures REDUCED distance Ventilation Boat Docks REDUCED Ventilation Boat Docks Appendages & structures REDUCED distance & protection at slopes >10% Ventilation REDUCED - soffit vents allowed Boat Docks Underfloor Enclosure Underfloor Enclosure Underfloor Enclosure REDUCED Exterior Walls REDUCED flashing Exterior Walls Exterior Glazing Exterior Doors *REDUCED items are a reduction compared to standard Proximity Zone A Ignition-Resistant (IR) Construction Requirements 10 Adoption Process • May 2024 through June 2024 – public engagement and various meetings • hosted June 26th , July 11th and January 22nd presentations to Building and Fire Board. Letter of Recommendation received January 23, 2025 for adoption of 2024 IWUIC, local amendments and updated map. Map to be updated within 1 year of adoption. • Received AIS on August 14, 2024 with negative impact due to Wildland Interface increases. 11 2024 International Wildland Urban Interface Code P r o p o s e d L o c a l A m e n d m e n t s Questions? Thank you for your time! 12 Current WUI Map Concerns: • Discrepancy created by using 40 acres of wildland for Zones A and B, versus 750 acres of wildland for Zone C • High risk areas of Austin are unprotected • Ease of application and determining site conditions Current Proximity Classes: Class A: Within 50’ of 40 acre+ wildland Class B: Within 150’ of 40 acre+ wildland Class C: Within 1.5 miles of 750 acre+ wildland 13 2015 WUI Map Shown visually similar to new map, with wildland shown in green 2024 WUI Map Including new “offset” or “buffer zone” visualization 14 Ember Ignition Zone (EIZ) Section 603.2.1 Wildfire Defense Mesh, IBHS Combustible Vs Non-Combustible Burn Demonstration • Right Side: Traditional wood deck, vegetation, wood mulch • Left Side: Noncombustible zone with ignition-resistant deck, Wildfire Defense Mesh skirting, rock mulch 15 Stakeholder Engagement Updates 07/03/2024 Changes in response to stakeholder feedback: • WUI Map – Option B, included in June 24 engagement, reduces Proximity Zone C • Driveways 403.2, clarified this section applies to buildings under the Residential Code • Wood roof coverings 503.2.3, clarification to include fire-retardant-treated wood in body of code • Fasciae 504.3.2, 505.3.2, 506.4.2, reduced minimum number of layers and clarified options • Gaps between materials 504.3.3, 505.3.3, 506.4.3, clarified this applies to all gaps in eave • Exposed rafter tails 504.3.4, 505.3.4, clarified exposed roof deck testing requirements are 30 minutes for Zone A and 10 minutes for Zones B and C • Roof Assembly 506.2, added missing number for Exception 4 • Exposed rafter tails 506.4.4, added option to use ignition-resistant material for rafter tails in Zone C • Exterior Ceilings 504.3.5, 505.3.5, 506.4.5, clarified this includes ceilings below a covered porch roof or below a deck/balcony/floor above • Fences 506.6.1, reduced requirement for residential Zone C fences to have ignition-resistant construction when located within 5’ of a building or structure, in lieu of 10’ 16 Post-Engagement Updates 07/09/2024 Additional update in response to stakeholder feedback: • WUI Map – Option C, reducing minimum wildland size to 20 acres in lieu of 10 acres. • EIZ 603.2.1 Ember Ignition Zone (EIZ), exception 5 added for Proximity Zone C to allow green, moist, closely mowed lawn grass, dormant grass shall be overseeded with perennial Rye. 07/25/2024: • Driveways 202 Definitions, 403.2, 403.2.3 applies to individual lots, not joint use driveways • WUI Map – Final • Retaining existing wildland size of 40 acres and 750 acres. • Zones A & B continue to be up to 50’ and up to 150’ from 40 acres of wildland, respectively • Zone C continues to be up to 1.5 miles from 750 acres of wildland, adding in a 0.5 miles from • Zones shown as “offsets” or “buffer zones” from wildland in lieu of an entire parcel being 40 acres of wildland shown as one zone. 17 18