Creating a Defensible Space for Wildfire Home Defense

What is defensible space?


Defensible space is the area around the property in which vegetation, debris and other types of combustible fuel or material have been treated, cleared or reduced to slow the spread of fire to and from a building.

The first step in achieving and maintaining defensible space is to get educated about how to create a defensible space. Cal Fire has some great articles and educational pieces about wildfires and defensible space you can find on their website.

According to Cal Fire’s defensible space guide, property owners that are near wildland-urban areas should maintain control of the 100 feet surrounding structures at all times. This area is known as the Home Ignition Zone (HIZ).

The Home Ignition Zone consist of three zones, each to be maintained to create an effective defensible space:


  • Clean roofs and gutters of dead leaves, debris and pine needles that could ignite from wind-blown embers.

  • Replace or repair loose or missing shingles or roof tiles to prevent ember penetration.

  • Install 1/8-inch metal mesh screening on eaves to prevent embers from passing through vents.

  • Clean debris from exterior attic vents and install 1/8-inch metal mesh screening to reduce embers.

  • Repair or replace damaged or loose window screens and broken windows. Screen or box in areas below patios and decks with wire mesh to prevent debris and combustible materials from accumulating.

  • Move any flammable material away from wall exteriors. Consider removing mulch, flammable plants, leaves and needles, firewood piles – anything that can burn.

  • Remove anything stored underneath decks or porches.


  • Clear vegetation from under large stationary propane tanks.

  • Create fuel breaks (spaces with no combustibles) using driveways, walkways and paths, patios and decks.

  • Keep lawns and native grasses mowed to no more than 4 inches tall.

  • Remove vertical fuels (vegetation under trees) so a surface fire cannot reach the crowns. Prune lower tree branches 6 to 10 feet from the ground.

  • Space trees to a minimum of 18 feet between crowns, increasing the distance as the slope on the property increases.

  • Plan tree placement to ensure the mature canopy is no closer than 10 feet to the edge of the structure.

  • Limit trees and shrubs to small clusters of a few each to break up the continuity of the vegetation across the landscape.


  • Dispose of heavy accumulations of ground litter/debris.

  • Remove dead plant and tree material.

  • Remove small conifers growing between mature trees.

  • Remove vegetation adjacent to storage sheds or other outbuildings within this area.

  • Plan or clear trees so that any 30 to 60 feet from the home have at least 12 feet between canopy tops.

  • Plan or clear trees so that any 60 to 100 feet from the home have at least 6 feet between the canopy tops.


If you are evacuated and do not know if you will be coming back to a home, you can give Allied Restoration a call for some prior consultations and home defense planning. Better yet, call Allied Restoration today to start planning your wildfire protection plan!

Allied Restoration is a NFPA (National Fire Protection Association) Member and can conduct a 14-point home defense inspection. Homeowners around the wildfire areas also sign up for the Private Client Home Defense plan where they can get access to our emergency services 24/7/365!

If you are interested in our 14-point inspection and Private Client Home Defense plan, give us a call at 888-860-1003 to schedule a free consultation.