Zone 0 defensible space

Zone 0 is the 0-5 foot area immediately surrounding your home. It's the most critical zone for surviving a wildfire because embers (not flame contact) cause most home ignitions.

In Zone 0, you should have zero combustible materials: no wood mulch, no dead vegetation, no wooden fences attached to the structure, no firewood, no propane tanks.

Think of Zone 0 as your home's fireproof shield. Use Trinetra's Zone 0 Inspection to have AI evaluate your property against EMBER compliance standards.

Creating a 5-foot buffer around your home:

• ·Remove all dead plants, leaves, and pine needles
• ·Replace wood mulch with gravel, decomposed granite, or river rock
• ·Trim branches that hang over or touch the roof or walls
• ·Remove vegetation that's touching or growing against the house
• ·Move planters with combustible plants at least 5 feet from walls

The goal is a non-combustible perimeter. Ember landing in wood mulch next to your wall is the most common way homes ignite in wildfires.

Fire-resistant ground cover options for Zone 0:

• ·Gravel or river rock (best — completely non-combustible)
• ·Decomposed granite (excellent, low maintenance)
• ·Concrete pavers or flagstone
• ·Succulent ground cover (ice plant, sedum — high water content)

Avoid: Wood mulch, bark chips, pine needles, rubber mulch (highly flammable), and dry decorative grasses within 5 feet of structures.

Fire-resistant plants share these traits: high moisture content, low oil/resin, and deciduous (vs evergreen).

Avoid near your home: Juniper, eucalyptus, pine, cedar, ornamental grasses — these are highly flammable due to oils and resins.

Maintenance schedule for defensible space:

• ·Zone 0 (0-5ft): Inspect monthly during fire season. Clear dead leaves, pine needles, and debris immediately. This is your highest priority.
• ·Zone 1 (5-30ft): Clear twice per year (spring and early fall). Trim trees 10ft from structures, remove dead plants.
• ·Zone 2 (30-100ft): Clear annually before fire season. Reduce fuel continuity, create spacing between trees.

After high winds, do an extra check — wind deposits debris fast. Use Trinetra's Zone 0 Inspection any time to verify.

Yes — wooden fences attached directly to your home are one of the top fire risks identified by EMBER.

A burning fence acts as a fuse, carrying fire directly from the wildland to your structure. This is called a "fire bridge."

If replacing the whole fence isn't practical, just breaking the connection point makes a significant difference.

If it's attached directly to your home, yes — or at minimum create a non-combustible break in the first 5 feet.

A wooden picket fence is highly vulnerable to ember ignition. During a wildfire, embers travel miles ahead of the fire and lodge in fence boards, igniting them. If that fence connects to your house, the fire follows.

Cost-effective approach: Replace just the section within 5 feet of the structure with metal fencing, and add a masonry or metal post as a fire break. The rest of the fence can remain wood.

Best fence materials for fire safety (ranked):

1. Masonry/cinder block — completely non-combustible 2. Steel/wrought iron — non-combustible, doesn't radiate enough heat to ignite nearby materials 3. Composite materials — some are fire-rated; check the manufacturer's specs 4. Aluminum — non-combustible but can melt in extreme heat

Even with fire-resistant fencing, keep vegetation cleared around the fence line. A non-combustible fence surrounded by dry brush still creates a fire pathway.

To reduce ember ignition risk for existing wood fences:

• ·Clear debris along the fence line — dry leaves and grass act as kindling
• ·Apply fire-retardant treatment to the wood (available at hardware stores)
• ·Create a non-combustible gap where the fence meets your home (replace the first 5ft with metal)
• ·Remove vegetation growing on or through the fence
• ·Close gaps at the bottom where embers can lodge

The critical fix is the connection point to your house. Even a 3-foot metal section between the wood fence and your wall dramatically reduces risk.

NFPA (National Fire Protection Association) guidelines:

• ·Tanks under 125 gallons: At least 10 feet from structures, property lines, and ignition sources
• ·Tanks 125-500 gallons: At least 10 feet from structures
• ·Tanks over 500 gallons: At least 25 feet

In wildfire-prone areas, consider going beyond minimum distances. Clear all vegetation within 10 feet of any propane tank. Keep the tank's relief valve pointed away from the structure. If evacuation is ordered, turn off the tank valve if it's safe to do so.

Fuel storage safety for fire-prone areas:

• ·Store gasoline in approved containers only (UL-listed red containers)
• ·Keep fuel at least 50 feet from structures if possible (10 feet minimum)
• ·Store in a detached shed — never inside your home or attached garage
• ·Keep containers in a cool, well-ventilated area away from ignition sources
• ·Store only what you need — don't stockpile large quantities

Propane tanks, gasoline cans, and even paint cans are fuel sources. During fire season, minimize what's stored close to home.

No — enclosing a propane tank can be dangerous:

• ·Propane tanks have pressure relief valves that vent gas if the tank overheats. An enclosure traps this gas, creating an explosion risk.
• ·Ventilation is critical for safety

Yes — wood mulch within 5 feet of your home is one of the most common fire entry points.

Wood mulch, bark chips, and pine straw are easily ignited by windborne embers. Once ignited next to your foundation or siding, the fire spreads to your structure.

Beyond 5 feet, wood mulch is lower risk but still worth replacing if you're in a high fire danger area.

Non-combustible alternatives ranked by effectiveness:

1. Gravel / river rock — completely non-combustible, low maintenance, excellent drainage 2. Decomposed granite (DG) — non-combustible, natural look, good for paths and beds 3. Concrete pavers or flagstone — permanent, non-combustible 4. Crushed rock — non-combustible, available in various colors

Not recommended: Rubber mulch (made from tires, highly flammable and toxic when burning), dyed wood mulch (still combustible).

The cost of replacing mulch with gravel is typically $100-300 and provides permanent fire protection.

No — rubber mulch is actually more dangerous than wood mulch near your home.

Rubber mulch (made from recycled tires) is highly flammable, burns at extremely high temperatures, produces toxic smoke, and is very difficult to extinguish once ignited.

Use gravel, river rock, or decomposed granite instead. These are completely non-combustible and require less maintenance than any organic or rubber mulch.

You can check right now using Trinetra's Zone 0 Inspection tool (Respond tab):

1. Walk around your home and use the checklist to log what you see 2. The EMBER AI analyzes your observations on-device 3. Take a photo for cloud verification via Gemini 4. Get an instant compliance score

EMBER (the AI model trained on real Zone 0 data) identifies these hazard classes:

• ·COMBUSTIBLE_FENCE — Wooden/picket fences attached to structures
• ·WOOD_MULCH — Bark, chips, or organic mulch within 5 feet
• ·PROPANE_TANK — Fuel storage too close to structures
• ·VEGETATION_BUFFER_5FT — Plants or dead vegetation within the buffer zone
• ·COMPLIANT — Area meets defensible space standards

EMBER was fine-tuned on 252 real property images and runs entirely on your device for privacy. It's a pre-screening — Gemini provides final cloud verification.

Several options from free to professional:

1. Trinetra Zone 0 Inspection (free) — Use the AI-powered tool in the Respond tab. On-device EMBER analysis + cloud Gemini verification.

2. Local Fire Department — Many departments offer free home assessments. Contact your local fire station.

3. Firewise USA Program — Community-based program with professional assessments. Check firewise.org.

4. Insurance Company — Some insurers offer assessments that can lower your premiums if you address findings.

Start with Trinetra's inspection — it's instant, private, and gives you specific findings to address.