What Is Defensible Space Around the Outside of My Home?

Tree Fire Mitigation Mountain Property

Defensible space is the term used for the space created between your home and the great area in your landscape with the purpose of providing more solid protection to your home in case of wildfires. The creation of such space has become increasingly important in recent years, since wildfires have been becoming more and more frequent and more and more severe, even in geographical areas that used to be safe from fires in the past. Here are some things that you should know about defensible spaces.

What Is, Exactly, a Defensible Space in the Context of Fire Protection and Prevention?

The term is used to denote the 100 feet wide area around a residential building that should be arranged based on certain principles developed to mitigate wildfire hazards. The area does not have to be completely free from vegetation, but it has to be free from combustible materials, clean and regularly maintained. Defensible space is usually divided in three zones:

  • Zone 0 – this term refers to the strip of land immediately around your building and stretching to the distance of 5 feet from the construction. Being so close to the building, the area needs extra attention and it should be kept free from any flammable materials, including door mats and garbage bins. The entire stretch should be cleaned regularly to remove any debris, dried tree leaves and twigs that could catch fire;
  • Zone 1 – this circle is located between 5-30 feet from the building and it usually includes the line where vegetation around the house starts. The zone needs to be kept well-maintained, free from combustible materials and vegetation properly cared for. It is very important to prune and trim the trees and shrubs in the zone and dead leaves, plant stems and dried flowers also need to be removed. Regularly mowing and watering the lawn is also important to make the turf resistant to fire;
  • Zone 2 – this circle is located between 30-100 feet from your building. Ideally, any structure in this area is built from fire-resistant materials and the vegetation in the zone also needs to be properly maintained. The trees and shrubs in this area should also be planted and trimmed with fire prevention mind, with the distance between the ground and the lowermost part of the vegetation being of at least 6 feet and the distance between a tree and a shrub should also be large enough to prevent the spreading of fires.

Other Prevention Measures to Maintain the Efficiency of Defensible Space

The careful selection of the plant varieties to be used in defensible zones and the installation of proper irrigation systems can significantly improve the level of safety provided by defensible zones. Some plant varieties are more resistant to fire than others, therefore they should be preferred in fire-prone zones, while the right type of irrigation method can insure that no part of the landscape is desiccated, therefore it will make the entire garden or yard stronger in front of wildfires.

To further enhance the efficiency of fire prevention methods, driveways and access roads should also be kept clean and free from obstacles to permit the access of firefighters if a wildfire cannot be stopped using other methods.