Defensible space basics: Zones 0, 1, and 2

California requires homeowners in fire-prone areas to maintain defensible space in three concentric zones around the home.

Zone 0 (0–5 ft): the ember-resistant zone. Noncombustible only.

Zone 1 (5–30 ft): the lean, clean, and green zone. Remove dead plants, prune trees, separate shrubs, and keep things short and irrigated.

Zone 2 (30–100 ft): the reduced-fuel zone. Thin trees and shrubs, remove ladder fuels, and keep grass cut.

Post-fire investigations consistently find that the majority of homes destroyed in a wildfire ignite from embers — not from direct flame contact with the structure.

Embers travel up to a mile ahead of the main fire. They land in gutters full of dry leaves, blow into open vents, and pile up against combustible siding. Defensible space is really ember-defensible space.

Start at Zone 0 and work outward. A perfectly maintained Zone 2 with a flammable Zone 0 is a house that loses to embers.

Then clean the roof and gutters of all needles, leaves, and debris. This is one of the highest-impact, lowest-cost fixes.

Then look at your vents (see our ember-resistant vents guide). After that, move outward into Zone 1 spacing and pruning.