Wildfire Zone Preparedness

The Wildfire Threat Has Changed

The wildfire behavior that destroyed 86 people in Paradise, California in 2018, and that has driven record losses in subsequent years, is fundamentally different from the slow-moving brush fires of decades past.

Modern high-intensity wildfires driven by drought, accumulated fuel, and high winds travel faster than most people can move. The Camp Fire spread at a rate of approximately 80 football fields per minute at its fastest. Warning times for affected homes were measured in minutes to low single-digit hours.

The preparations that determine whether your home survives are made months and years before the fire arrives, not when you see smoke.

Defensible Space: The 100-Foot Standard

California's defensible space law and fire science generally support a 100-foot minimum of managed vegetation around structures. This space is divided into zones:

Zone 1 (0-30 feet): Lean, Clean, and Green

• Remove all dead plants, grass, and weeds
• Create horizontal spacing between plants and trees (no continuous fuel path to the house)
• Remove branches within 10 feet of the ground on all trees
• Remove any plants that are immediately adjacent to the house structure
• Clear gutters of all debris
• Space plants so they're not touching and not forming a continuous fuel ladder

Zone 2 (30-100 feet): Reduce Fuel

• Mow grasses to 4 inches or lower
• Space shrubs so that fire spreading through them will not necessarily reach the house
• Space trees at least 18 feet crown-to-crown in flat areas; more spacing on slopes (fire travels faster uphill)
• Remove dead branches and debris

Slopes amplify fire intensity: On slopes steeper than 20%, the effective fire spread rate increases dramatically. Properties on slopes require more aggressive clearance in Zone 1 and 2 to achieve equivalent protection.

Home Hardening

The ember entry problem: Most homes that burn in wildfires ignite from embers entering through vulnerable points, not from direct flame contact. The hardening priorities address ember entry:

Roof:

• Class A fire-rated roofing material (asphalt shingles, metal, concrete tile) instead of wood shakes
• No wood shake roofs in WUI areas — they're essentially pre-ignited
• Metal drip edge and flashing on all roof penetrations

Vents:

• Replace standard vents with ember-resistant vents (1/16" metal mesh or commercial ember-resistant vent products)
• Attic vents, foundation vents, and eave vents are all potential ember entry points
• Retrofit with mesh screens where full vent replacement isn't feasible

Gutters:

• Clean gutters before fire season and after any significant wind event
• Metal gutters are preferred over plastic (less flammable)
• Gutter guards help but still require occasional inspection and cleaning

Deck and porch:

• Composite or metal decking is more fire-resistant than wood
• Close gaps between deck boards and under-deck space (ember accumulation)
• No storage of combustibles under decks

Windows and doors:

• Dual-pane or tempered glass resists thermal breakage from radiant heat
• Metal door thresholds and weather stripping on exterior doors
• Garage door seals

The Evacuation Trigger System

The READY-SET-GO evacuation framework (used by many California counties and widely adopted):

READY (Watch/Advised): Fire or other emergency in your general area. Prepare to leave. Get your go bag; make sure your car has fuel; know your route.

SET (Warning/Threatened): Threat approaching your area. You should leave now if you have elderly, disabled, or children to care for; if you have livestock; if you rely on others for transportation; if you're on a slow-to-exit road.

GO (Order/Evacuation): Mandatory evacuation order. Leave immediately.

The planning insight: If you wait for the GO order to start your evacuation, you may be leaving with everyone else simultaneously. The SET stage is when most fires-safety-conscious residents choose to leave.

Your personal trigger: Define in advance when you personally will leave. "I will leave when [specific condition]" — not "when it seems serious enough." Fire conditions can change in minutes. Having the trigger pre-defined removes the in-the-moment debate.

Go Bag and Vehicle Staging

When fire season begins, your go bag should be:

• Fully packed
• In or directly adjacent to your vehicle
• Go bag contents reviewed and updated from last year

Vehicle staging:

• Fuel tank at least 3/4 full at all times during fire season
• Vehicle parked pointing toward the exit (not backed in)
• Livestock trailer attached or immediately attachable if you have animals

The 30/10/Go-Now trigger:

• 30 minutes: Set phase. You have 30 minutes to prepare before leaving.
• 10 minutes: Warning. You have 10 minutes. Focus only on essential grab-and-go.
• Go Now: Leave immediately. Don't stop for anything.

Livestock and Large Animals

Livestock are often the reason people delay evacuation fatally. Animals cannot be loaded and moved in minutes; the process takes time.

Before fire season:

• Know which trailer you'll use and confirm it's roadworthy
• Practice loading animals so they're accustomed to it
• Identify two or three locations (fairgrounds, neighboring property outside your zone) where you can temporarily board animals
• Identify and have contact for a large animal veterinarian in your region

The decision threshold: If you have animals that require a trailer and you're in a fire-risk area, your evacuation trigger should be earlier than for a family without animals. The time to load animals is time you don't have when fire is visible.

After the Fire Passes

If your home survived and you return:

• Do not assume the structure is safe until visually confirmed; fires can smolder in wall cavities for hours
• Check for hot spots in debris, attic, walls — these can reignite
• Ash and debris on surfaces contain toxic compounds; use N95 or better respiratory protection when cleaning up
• Water from damaged distribution lines may not be safe; use stored water or bottled water until system is cleared