The method
How this tool reaches its answer
California law and Cal Fire guidance split defensible space into zones, and they are not arbitrary: home losses in a wildfire are driven more by embers than by a wall of flame. The 0–5 ft zone immediately around a structure is the ember zone. From 5 to 30 ft the aim is a lean, clean and green area — no ladder fuels to carry a ground fire into the crowns. From 30 to 100 ft the fuel load comes down, thinned and separated. Public Resources Code section 4291 requires that 100 ft of defensible space, or to the property line if that comes first.
This checker walks those three zones, asks about the conditions that actually defeat them — needle litter in a gutter, a closed-cone pine over a deck, a propane tank under a eucalyptus — and returns what to fix first. It is a checklist, not an inspection, and not a permit.
For the Cambria coast the local conditions make two items matter more than most: pines that hold deadwood and closed cones, and properties where the lot line arrives long before the 100 ft mark. Both are why a written clearance plan is worth having on file.
The three defensible space zones
Rates and bands last reviewed October 2026 · coastal San Luis Obispo County market rates
| Zone | Distance | The aim |
|---|---|---|
| Zone 0 — ember | 0–5 ft from the structure | Nothing combustible against the wall: no shrubs under vents, no litter in the gutter, no firewood on the deck. |
| Zone 1 — lean, clean, green | 5–30 ft | Remove dead material, break up ladder fuels, space and separate shrubs and trees. |
| Zone 2 — reduced fuel | 30–100 ft (or to the property line) | Thin trees, create crown separation, keep grass short and remove slash. |
Before you answer each screen
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Zone 0 — the five feet
- Anything combustible against the wall — a shrub under a vent, a stack of doormats, firewood — is a path for a windblown ember to reach the building.
- Needles in a gutter are the classic ignition point on a pine-covered lot, and they are the cheapest thing on this whole list to fix.
- A spark arrestor and a screened vent cost almost nothing and close two of the commonest entry points on a coastal house.
- Zone 0 work is a weekend of raking and screening rather than a contractor job, which is exactly why it comes first.
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Zone 1 — five to thirty feet
- Ladder fuel is anything that lets a ground fire climb: brush under the canopy, low dead branches, a stack of slash against a trunk.
- Ten feet of separation between crowns is the working number, and on a tight coastal lot that usually means thinning rather than removing.
- Raising the crown and pulling the brush is most of this zone, and it is usually done without losing a tree.
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Zone 2 — thirty to one hundred feet
- A steep slope runs fire uphill fast, so the clearance distances want widening on the uphill side of the house.
- Over six inches of needle duff is a slow, hot, smouldering fuel bed that keeps a fire alive long after the flame front has passed.
- Resinous pines, cypress and eucalyptus carry the highest ember and flame load, so they are thinned hardest and kept furthest out.
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Your parcel line
- Public Resources Code 4291 requires a hundred feet, so on a small coastal lot the outer zone often ends at a fence.
- What sits over the boundary matters as well: a neighbour's pine shedding into your gutter is still your gutter.
- Documenting the work matters as much as doing it, because the inspection is of the record as much as of the ground.
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Your clearance report
- This is a checklist and not an inspection or a permit: enforcement sits with the local fire authority and Cal Fire.
- Work you can do yourself is separated from work that needs a crew, a rope or a chipper.
- Keep the completed checklist with the parcel papers — it is what you show when the inspection notice arrives.
What the tool cannot know
A browser cannot see a tree. Decay inside a trunk or a root plate, soil and drainage, hidden utilities, access and crane reach, permits, protected species and boundaries are confirmed on site or not at all — which is why every figure here is a range with its method beside it, and why the only price that binds anybody is a written one after a walk-through.