Defensible Space is a strategy of building buffer zones around your house of managed landscaping that lowers your risk of your home succumbing to wildfires. Defensible spaces can be required by law and insurance agencies.
The state requires that homes in a high fire risk zone or higher to undergo a defensible space inspection. Learn more about this inspection in the following videos.
Learn what to expect during an inspection.
Click each zone to learn about the various Defensible Space Zones
While not legally required yet, Zone 0 is key for wildfire defense and preventing fires from spreading to your home. Here are the current guidelines:
Use gravel, pavers, or concrete instead of combustible mulch
Clear dead weeds, grass, and debris; check roofs, gutters, and outdoor areas
Keep branches trimmed 10 feet away from chimneys and stovepipes
Minimize combustible items like furniture and planters on decks
Move firewood and lumber to Zone 2 for safety
Replace combustible fencing and gates with fire-resistant materials
This could include wood and vinyl fencing material; including when combustible materials are used only as attachments between the house and non-combustible material such as metal. i.e. homeowner did not receive Wildfire Home Prepared Certification despite having a metal gate because the gate was attached via a wooden 2x4.
Shift garbage and recycling containers to a safer area outside this zone
Relocate boats, RVs, and vehicles away from this zone to reduce fire risks
Zone 1 extends 30 feet from buildings, structures, decks, etc. or to your property line, whichever is closer.
Clear all dead plants, grass, and weeds
Remove dead leaves and pine needles from your yard, roof, and gutters
Trim overhanging branches and keep them 10 feet from your chimney
Regularly trim trees to maintain a 10-foot gap from others
Move wood piles to Zone 2
Prune flammable plants and shrubs near windows
Clear flammable vegetation and items from under decks, balconies, and stairs
Maintain space between trees, shrubs, and flammable items like patio furniture and wood piles
Ensure outbuildings and LPG tanks have 10 feet of clear space to bare soil and no flammable vegetation within an additional 10 feet around them
Zone 2 extends from 30 feet to 100 feet out from buildings, structures, decks, etc. or to your property line, whichever is closer.
Trim annual grass to a maximum height of 4 inches
Space out shrubs and trees horizontally (See Horizontal Spacing Section)
Ensure vertical spacing between grass, shrubs, and trees (See Vertical Spacing Section)
Remove fallen leaves, needles, and small branches, but can leave up to 3 inches
Keep exposed wood piles at least 10 feet clear from surroundings, down to the soil
Ensure outbuildings and LPG tanks have 10 feet of clear space to bare soil and no flammable vegetation within an additional 10 feet around them
Maintain space between the lowest tree branches and the ground or shrubs.
Remove all tree branches at least six feet from the ground.
Allow extra vertical space between shrubs and trees. Lack of vertical space can allow a fire to move from the ground to the brush to the treetops like a ladder. This leads to more intense fire closer to your home.
Keep at least three times the height of any shrubs between the shrubs and the lowest branches of trees.
Example: A 5-foot shrub is growing near a tree. 15 feet of clearance is needed between the top of the shrub and the lowest tree branch.
How much space should you leave between trees or shrubs?
Horizontal space depends on the slope of the land and the height of the shrubs or trees. Leave more space between vegetation on bigger slopes. Refer to the chart below to determine spacing distance.
Space between shrubs:
Flat or mild slope (less than 20%): Two times the height of the shrub.
Mild to moderate slope (20-40%): Four times the height of the shrub
Moderate to steep slope (greater than 40%): Six times the height of the shrub
Space between trees:
Flat or mild slope (less than 20%): 10 feet.
Mild to moderate slope (20-40%): 20 feet.
Moderate to steep slope (greater than 40%): 30 feet