Critical Prep to Protect Your Home

1. Measure Your Zone 

• • Use a tape measure to mark the 5-30 foot perimeter around your home. Once marked, follow the steps below to manage vegetation, large items, and detached structures to eliminate connective fuels. 

2. Vegetation Maintenance (Trees, Shrubs, Yard) 

Tree Spacing 

• • 6-foot Vertical Clearance: Regularly maintain at least 6 feet of clearance between the ground and the lowest branches, or 1/3 of the tree’s total height if the tree is shorter than 18 feet. 
  • Example: If a tree is 15 feet tall, 1/3 of its height is 5 feet, so prune lower branches to create at least 5 feet of clearance.  
  • 10-foot Horizontal Clearance: Standard tree spacing is at least 5 feet from the home, 10 feet apart between individual canopies, and 10 feet from any chimney or stovepipe.  
  • You may have clustered trees if the combined canopy width is trimmed to 10 feet or less, treat the cluster as a single canopy when measuring.  
  • Breakup continuous rows or large clusters of trees by trimming canopies or removing select trees to maintain the proper spacing. 
  • Safety tip: If branches are near power lines, contact your utility provider to remove them, never attempt this yourself. 

Shrub Spacing 

• • Plant Selection: Choose low-growing, native, fire-resistant plants, and space them based on their mature size. When ignited by wildfire, shorter plant heights help reduce flame length (which bend in high winds), and adequate spacing slows fire spread.  
  • Foliage: Identify each shrub or cluster (treated as one shrub) you want to measure and space. Treat a group of shrubs growing close together as one cluster. Keep them trimmed to 10 feet wide or less.  
  • Horizontal Spacing is determined by shrub height. The standard spacing is 10 feet apart.   
  • If you prefer, you can calculate a smaller horizontal spacing based on shrub height. Measure the height of the tallest plant, then multiply that height by 2 to determine the minimum spacing neighboring shrubs should be placed.  
  • Example: If the tallest shrub is 4 feet tall, multiply 4 × 2 = 8 feet. In this case, shrubs should be at least 8 feet apart.  
  • Tip: Shorter shrubs need less spacing, so keep shrubs trimmed to maintain smaller spacing. 
  • If the shrubs are too close, trim or relocate some to create proper spacing. Breakup continuous hedge rows or privacy screens by removing enough plants to maintain adequate spacing between the remaining shrubs. 
  • Avoid Ladder Fuels: Relocate shrubs from beneath tree canopies to prevent fire from climbing up into the crown.   

Yard Maintenance 

• • Grass Height: Keep grass cut to less than 4 inches (or under 18 inches on slopes for erosion control).  
  • Remove Dead Vegetation: Regularly clear all dead or dying grass, weeds, plants, shrubs, trees, logs, stumps, branches, leaves, and pine needles.  
  • Firewood Storage: Store firewood and wood piles at least 30 feet from the home. 

3. Large Items 

Liquid Propane Gas (LPG) & Fuel Tanks 

• • Option 1: Locate the tank at least 30 feet from the home. 
  • Option 2: If Option 1 is not possible, place the tank at least 10 feet from the home and follow these guidelines: 
  • From 0-10 feet around the tank: Remove all vegetation, groundcover, and combustible items (e.g., fences). Instead, use noncombustible hardscape (e.g., gravel, pavers, river rock, DG, or concrete) or maintain bare soil.  
  • From 10-20 feet around the tank: Cut grass to less than 4 inches and remove plants, shrubs, small trees, and dead vegetation (e.g., limbs, logs, and stumps). Healthy, mature trees may remain but should be pruned to have clearance at least 6 feet above the tank. 

Hot Tub Placement & Surface 

• • Place hot tub at least 10 feet from the home and any other large combustible items.  
  • Do not install it under a combustible overhead structure (e.g., covered porch, pergola, or gazebo).  
  • If installed on a combustible deck (e.g., wood or composite), replace the deck boards directly beneath the hot tub with a noncombustible surface extending at least 2 feet around it. 
  • If installed on a noncombustible patio (e.g., concrete or pavers), maintain a 0–5 Foot Noncombustible Zone around the hot tub. 

Outdoor Kitchens, Bars, & Built-Ins 

• • Construct entirely with noncombustible materials (e.g., stone or metal). 
  • If attached to the home, apply at least 6 vertical inches of noncombustible material (e.g., backsplash or siding) on the wall directly above any horizontal surface.   

Combustible Water Storage Tanks 

• • Place tanks at least 5 feet from the home and other large combustibles.  
  • Multiple tanks may be placed within 5 feet of each other.  
  • Do not place under a combustible overhead structure (e.g., covered porch, pergola, or gazebo).
  • Maintain a 0–5 Foot Noncombustible Zone beneath and around each tank. 

4. Detached Structures (10-30 Feet from the Home) 

Placement & Quantity 

• • Place detached accessory structures (e.g., freestanding pergolas, sheds, playsets, Accessory Dwelling Units [ADUs]) at least 10 feet from the home, decks, and from each other.  
  • Exception: Fully noncombustible metal pergolas do not have spacing requirements.  
  • Limit to three total structures within this zone. 

Roof Covering 

• • Freestanding Pergolas: Remove combustible roof slats (e.g., wood or vinyl) to ensure no more than 15% coverage of the total surface area.
  • Tip: For 2x boards (e.g., 2×4, 2×6 turned on the 2x edge), allow approximately 1-foot spacing between boards.  
  • Solid Roofs: Use Class A fire-rated materials (e.g., asphalt shingles, concrete/clay tile, slate, or metal).  
  • Avoid combustible coverings such as wood, plastic corrugated panels, and fabric shades. 

Noncombustible Base Material & Zones 

• • Each structure must have its own 0–5 Foot Noncombustible Zone that does not overlap with others. 
  • Apply 6 vertical inches of noncombustible material at the base of each combustible structure and its posts. 
    • Examples:  
      • Elevated Sheds: Enclose the underside with noncombustible material (e.g., 1/8-inch metal mesh, stone, concrete blocks, or brick).  
      • Wood Playsets: Apply corrosion-resistant metal flashing at the base of each post.

Open Structures (e.g., Carports & Garages) 

• • Do not store combustible items inside.  
  • If interior walls have exposed combustible material (e.g., wood), the structure should be fully enclosed. 

1. Check & Maintain a Class A-Rated Roof 

• • Confirm your roof is Class A fire-resistant rated. Most asphalt shingles, tile, slate, and metal roofs meet this testing standard.  
  • Note: Barrel tile and corrugated metal roofs with open gaps should include noncombustible bird stops at the edges to prevent ember intrusion and debris ignition. 
  • Replace wood or other non-rated materials with a Class A fire-resistant-rated roof to significantly reduce fire risk.  
  • Regularly clear leaves, pine needles, and other debris from the roof.  

2. Check & Maintain Gutters 

• • Regularly clear gutters and downspouts of all vegetative debris.  
  • Replace plastic or PVC gutters with noncombustible metal options, such as aluminum or steel.

3. Upgrade or Retrofit Vents to Resist Embers 

• • Install flame- and ember-resistant vents with proper sealants or retrofit existing vents by covering them with 1/8-inch corrosion-resistant metal mesh at roof openings, attic, soffits, wall vents, and crawlspace or underfloor vents (if applicable).  
  • Ensure dryer vents have functional louvers or a self-closing flap to block ember entry. 
  • Note: Do not use metal mesh on dryer vents, as it can trap lint and pose a fire hazard. 
  • Inspect for damage and clean vent screens regularly to remove leaves, debris, and lint buildup. 

4. Ensure 6-Inch Noncombustible Clearance at Exterior Wall Base 

• • Ensure at least 6 vertical inches of noncombustible siding material is applied at the base of all exterior walls and above any attached surfaces such as a deck or patio. 
  • Acceptable materials include exposed concrete foundation, fiber-cement siding, brick, stone, stucco, or metal flashing.

5. Maintain Attached Patios, Decks and Overhead Structures  (e.g., covered porches, pergolas, carports, and gazebos) 

Around the Structure 

• • Ensure attached structures have the 0–5 Foot Noncombustible Zone, measured from the outermost posts. 
  • Note: A fully noncombustible patio surface (e.g., concrete slab or pavers) with no cover, or with a fully noncombustible pergola (e.g., metal), does not require this zone.  

Top of Walking Surfaces 

• • Clear all vegetative debris, planter boxes, and climbing vines.  
  • Limit to no more than 10 small, noncombustible potted plants (e.g., clay or ceramic). Each should be less than 36 inches tall (including the pot) and easy to move indoors during Red Flag Warnings or extended absences.   
  • Use noncombustible-framed furniture (e.g., cast iron, aluminum or metal). Remove combustible furniture such as wood, composite wicker, or plastic, including hanging chairs, lounge or rocking chairs, swinging benches, picnic tables, and sectional seating.  
  • Keep cushions and other combustible accessories to a minimum and store indoors during Red Flag Warnings or extended absences. 
  • Keep the area within 5 feet of the home clear of combustible items such as firewood, large rugs, storage containers, and shade screens.  
  • Relocate movable items like trash bins, doormats, garden hoses, or BBQ grills indoors or at least 30 feet away during Red Flag Warnings or extended absences.  

Attached Overhead Structures (e.g., covered porches, pergolas, carports) 

• • For attached combustible pergolas, remove roof slats (e.g., wood or vinyl) to ensure no more than 15% coverage of the total surface area. 
  • Tip: For 2x boards (e.g., 2×4, 2×6 turned on the 2x side), allow approximately 1-foot spacing between boards.  
  • Note: For freestanding pergolas see “5-30 Foot Defensible Space Zone”. 
  • For attached solid roof covered porches, use a solid Class A fire-rated roof covering such as asphalt shingles, concrete/clay tile, slate, or metal; avoid wood roofs, plastic corrugated panels, and fabric shades. 
  • Apply at least 6 vertical inches of noncombustible wall covering (e.g., metal flashing, fiber-cement, masonry veneer or stucco) at the base of any combustible home siding and structure posts. 
  • Keep attached structures free of combustible items such as hanging vegetation, curtains/drapes, combustible furniture, shade screens, and stored items; shade screens that fully retract into noncombustible housing may be used. 
  • Avoid storing combustible items inside attached open structures (e.g., carports and garages); if interior walls have exposed combustible material (e.g., wood), enclose the structure. 

Underneath an Elevated Deck 

• • Remove all stored items from beneath the deck and stairs, including firewood, lumber, outdoor equipment, tools, ladders, and kayaks. If used as an open outdoor living area, follow best practices from the Top of Walking Surfaces section. 
  • Clear all vegetation and combustible groundcover, including grass, weeds, plants, exposed weed cloth, artificial turf, and wood mulch within the 0–5 Foot Noncombustible Zone beneath and around the deck and stairs. Replace with noncombustible hardscape such as bare soil, gravel, pavers, river rock, decomposed granite (DG), or concrete. 
  • Apply at least 6 vertical inches of noncombustible material at the base of combustible deck posts, supporting walls, and stairs using materials like metal flashing, fiber-cement, masonry veneer, or stucco. For combustible lattice, remove the bottom 6 inches or replace with noncombustible material, and install 1/8” or finer metal mesh on the outside of the lattice to help reduce debris buildup and ember intrusion. 
  • Decks 4 Feet or Less above ground level: Enclose the underside to prevent ember and debris accumulation using 1/8-inch or finer metal wire mesh from the outer edge of the walking surface to the ground. 
  • Note: Install the metal mesh on the outside of any existing lattice.