Definition of Terms:
Vents protected with mesh:
Up to 90% of structure loss during the wildfire is from ember intrusion. Embers enter structures through attic vents, foundation vents, open under floor spaces etc. These openings can easily be protected using a non combustible mesh, or screen with openings that are 1/8th or smaller.
Vegetation 0-5 ft clearance:
The 0-5 foot noncombustible zone is a critical wildfire safety measure. It is a buffer zone around structures designed to prevent ember ignition and the spread of fire from both direct flame contact and radiated heat. This zone, also known as Zone 0 or the Ember-Resistant Zone, should be free of any flammable materials like mulch, woodpiles, or vegetation. It’s essentially a 5-foot area around the structure where only non-combustible materials like gravel, concrete, or pavers are allowed
Vegetation 5-30 ft clearance:
The 5-30 ft zone extends from 5 feet from the structure to 30 feet. This zone is also referred to as Zone 1 and is required to be maintained around structures located in the Very High Fire Hazard Severity Zone as identified by the State of California. In this zone, remove dead vegetation and debris and maintain spacing between shrubs and trees. Remove “ladder fuels” (i.e. trees or shrubs that are growing under other trees) because they can increase the probability of fire moving into the tree canopy. Keep vegetation in this zone irrigated. Hardscape and plant islands or beds can help maintain horizontal separation to reduce the spread of fire.
Vegetation 30-100 ft clearance:
The 30-100 ft zone extends from 30 feet from the structure to 100 feet. This zone is also referred to as Zone 2 and is required to be maintained around structures located in the Very High Fire Hazard Severity Zone as identified by the State of California. The objective of this zone is to reduce fire spread and restrict fire movement into the crowns of trees or shrubs. Remove dead plant material, lower tree branches and other ladder fuels (e.g., shrubs, lower branches, smaller trees)
Gutters, scuppers and downspouts:
Gutters, scuppers and downspouts are parts of a system to catch rainwater from the roof of a structure and move it away from the structure. Gutters are channels mounted at the edge of the roof to capture the water. Scuppers are openings in parapet walls on flat roofs to allow water to drain from the roof. Downspouts are attached to gutters and scuppers to bring water from the roof’s edge to the ground and out away from the structure.
Clean gutters:
Rain gutters, scuppers, and downspouts will gather debris such as leaves, pine needles and twigs that have landed on the roof. This debris becomes dry and brittle and easily ignitable from embers causing flames against the edge of the roof. Gutters need to be maintained free of this debris. The installation of non combustible gutter guards helps prevent this debris from gathering.
Building non-combustible:
Non-combustible building materials are those that do not burn or ignite when exposed to heat or fire. Examples include brick, concrete, steel, stone, glass and gypsum. Windows installed as part of a non-combustible building are often dual panes with tempered glass.
Overgrown vegetation:
Overgrown vegetation is vegetation that has not been maintained and contains excessive amounts of leaves, needles and dead foliage. This excessive amount of foliage contributes to extreme fire behavior producing larger flames, radiant heat, and increased ember production.
Vegetation spaced out:
Vegetation spacing refers to separating plant species from each other, or in small, planting groupings to prevent fire spread from plant to plant. Often times this involves spacing plants apart from each other twice the distance as their height.
