What is Defensible Space?
Defensible space is the space you create between a building on your property and the grass, trees, shrubs, or any wildland area that surrounds it. Defensible space is essential to improve your home's chance of surviving a wildfire. This definition is provided by FIRESafe Marin on the defensible page page of their website. A full description of these recommendation can be found on the FIRESafe website. They define three zones for particular focus:
Within 5 feet of the home: Otherwise known as Zone 0, there should be zero combustibles in this zone. Remove plants within this zone where possible; replace mulched areas with noncombustible ground cover, such as gravel. Remove tree limbs that extend into this zone. Do not store firewood or other combustibles here, especially under decks or overhangs.
Within 30 feet of the home: Within Zone 1, remove all dead grass, weeds, plant and foliage. Remove shredded bark used as mulch (otherwise known as "gorilla hair"). Use only heavy bark mulch or compost. Chose only fire-smart plants for this area. "Limb up" or trim tree limbs to 6 to 10 feet above the ground. Eliminate tree branches within 10 feet of the roof or chimneys.
Within 30-100 feet of the home: In Zone 2, the recommendations vary depending on how hilly your plot is. Cut or mow annual grasses to no more than 4 inches. Create horizontal space between shrubs and trees to limit the spread of flames. Create vertical space between grass and shrubs to trees, to limit the "laddering" of flames from one level to the next. Maintain the space well to remove fallen leaves, needles and small branches.
Beyond 100 feet of the home: Within Zone 3, focus on vegetation adjacent to roads and driveways to ensure access by emergency vehicles. Clear vegetation to at least 14 fee overhead and 10 feet from sides of roads, maintaining a 12 foot width for all roadways. Ensure that street address numbers are visible with at least 4 inch reflector numbers.
Within 5 feet of the home: Otherwise known as Zone 0, there should be zero combustibles in this zone. Remove plants within this zone where possible; replace mulched areas with noncombustible ground cover, such as gravel. Remove tree limbs that extend into this zone. Do not store firewood or other combustibles here, especially under decks or overhangs.
Within 30 feet of the home: Within Zone 1, remove all dead grass, weeds, plant and foliage. Remove shredded bark used as mulch (otherwise known as "gorilla hair"). Use only heavy bark mulch or compost. Chose only fire-smart plants for this area. "Limb up" or trim tree limbs to 6 to 10 feet above the ground. Eliminate tree branches within 10 feet of the roof or chimneys.
Within 30-100 feet of the home: In Zone 2, the recommendations vary depending on how hilly your plot is. Cut or mow annual grasses to no more than 4 inches. Create horizontal space between shrubs and trees to limit the spread of flames. Create vertical space between grass and shrubs to trees, to limit the "laddering" of flames from one level to the next. Maintain the space well to remove fallen leaves, needles and small branches.
Beyond 100 feet of the home: Within Zone 3, focus on vegetation adjacent to roads and driveways to ensure access by emergency vehicles. Clear vegetation to at least 14 fee overhead and 10 feet from sides of roads, maintaining a 12 foot width for all roadways. Ensure that street address numbers are visible with at least 4 inch reflector numbers.