Under Oregon State Fire Marshal (OSFM) guidelines, defensible space is divided into three concentric rings radiating outward from your home:

Zone 1: Non-Combustible Buffer (0 to 5 Feet)

The Goal: Prevent windborne embers from igniting the immediate base of your home.
Key Actions: Replace bark mulch or wood chips with gravel, river rock, or concrete pavers. Remove dry leaves, pine needles, and dead vegetation. Never store firewood, propane tanks, or flammable outdoor furniture cushions within this 5-foot perimeter.
Zone 2: Lean, Clean & Green (5 to 30 Feet)

The Goal: Eliminate continuous fuel beds that could carry surface flames directly to the house.
Key Actions: Keep lawns mowed under 4 inches. Prune low-hanging tree limbs up to 6 feet from the ground (or up to 1/3 the tree’s total height for smaller trees). Space shrubbery so plant canopies do not touch, and move firewood piles at least 30 feet away from any structure.
Zone 3: Forest Thinning & Reduced Fuel (30 to 100+ Feet)

The Goal: Interrupt canopy fires and slow down approaching fire intensity.
Key Actions: Thin dense tree clusters so tree crowns maintain at least 10 feet of horizontal separation. Remove dead fallen timber, thick underbrush, and "ladder fuels" (small saplings or shrubs growing directly beneath mature tree canopies).

Windborne embers carry miles ahead of an active fire front and cause over 80% of home ignitions during wildfires. Hardening the structure reduces ember risks:

Roof & Gutter Clearing: Conifer needles and dry leaves accumulate in roof valleys and rain gutters, creating an easy ignition point. Clean gutters regularly or install non-combustible gutter guards.
Vent Protection: Standard attic and crawlspace vents can draw embers inside wall cavities. Cover all exterior soffit, gable, and foundation vents with 1/8-inch non-combustible metal wire mesh.
Decks & Fences: Clear debris from on top of and beneath wooden decks. Where a wooden fence connects directly to a house, install a 5-foot non-combustible gate or metal section to break the continuous fuel path to your siding.

Securing property insurance in wildfire-prone areas has become a significant step in the real estate transaction process. Lenders require active hazard insurance before funding a mortgage.

Carrier Inspection Requirements: Many national insurance carriers conduct pre-binding exterior inspections or use aerial imagery. Coverage may be conditioned on clearing hazard trees, creating a 30-foot brush clearance, or replacing wood shake roofs.
Proof of Mitigation Discounts: Under Oregon Division of Financial Regulation (DFR) guidelines, insurers are encouraged to account for risk reduction. Documenting defensible space work, tree thinning, or Firewise USA community certification can help maintain coverage or unlock premium discounts.
The Oregon FAIR Plan (Insurer of Last Resort): If standard market carriers decline coverage due to wildfire scoring, buyers can access the Oregon FAIR Plan. This state-mandated safety net provides basic property coverage, ensuring transactions can close even in higher-risk zones.
Buyer Tip: Start shopping for homeowners insurance immediately upon going under contract—do not wait until the final week of escrow.

Oregon State Fire Marshal Defensible Space Program — Technical guidelines, plant lists, and requests for free local defensible space assessments.
Firewise USA Site Directory — Find or register local neighborhood Firewise USA recognized communities.
Oregon Division of Financial Regulation (DFR) Wildfire Insurance Guide — State consumer resources, insurance advocate assistance, and FAIR Plan information.