3 Key Zones
A defensible home has the greatest potential for survivability in the event of a wildfire during average wind conditions. Defensible homes are those that are in compliance with “defensible space” requirements or a fuel modification program and have been “hardened” in accordance with Chapter 7A of the California Building Code.
What Is Defensible Space?
Defensible space is the required distance between a structure and the wildland area that, under normal conditions, creates a sufficient buffer to slow or halt the spread of wildfire to a structure. It protects the home from igniting due to direct flame impingement and radiant heat. Compliance is essential for structure survivability during wildfire conditions. Defensible space requirements apply to all structures regardless of the year built.
The home and the area 0–5 feet from the furthest attached exterior point of the home. This zone should be kept free of combustible materials.
Keep lawns mowed and well-maintained. Use well-spaced plantings of low flammability species, swap mulch for rock, gravel, or stone, and remove large fuel packages such as firewood piles from this area.
The area 5–30 feet from the furthest exterior point of the home. Manage plants and hardscape features here to reduce the chance of flames reaching the structure.
Keep irrigated with low-growing, low-flammable plants. Create separation between grasses, shrubs, and trees to avoid fire spreading into taller vegetation in a “fuel ladder” effect, and space trees to prevent crowns from touching.
Landscaping and outlying vegetation managed to reduce fuel and slow fire spread as it approaches Zone 1 and the home.
Place low-growing plants and well-spaced trees, and keep the overall volume of vegetation (fuel) low to slow fire spread as it moves toward the home.