Home Assessment Tips

Home Ignition Zone (HIZ)

What is the Home Ignition Zone?

Home Ignition Zone refers to the area immediately surrounding a home where vegetation and other potential fuel sources are managed to reduce the risk of ignition during a wildfire.

Zone One - extends 30 feet out from buildings, structures, decks, etc.

  • Remove all dead or dying vegetation.

  • Remove “ladder fuels” (low-level vegetation that allows the fire to spread from the ground to the tree canopy). Create at least 6 feet of separation between low-level vegetation and tree branches. This can be done by reducing the height of low-level vegetation and/or trimming low tree branches.

  • Create “fire-free” area within 5 feet of home, using non-flammable landscaping materials and/or high-moisture content, drought-resistant vegetation.

  • Trim tree canopies regularly to keep their branches a minimum of 10 feet from structures and other trees.

  • Remove leaf litter (dry leaves/pine needles) from yard, roof and rain gutters.

  • Relocate woodpiles or other combustible materials into Zone Two.

  • Remove combustible material and vegetation from around and under decks, lanai, or the entire house if foundation is post-and-pier.

  • Remove or prune vegetation near windows.

Zone Two - extends 30 to 100 feet out from buildings, structures and decks. You can minimize the chance of fire jumping from plant to plant by removing dead material and removing and/or thinning vegetation. The minimum spacing between vegetation is three times the dimension of the plant.

  • Remove “ladder fuels.” (pictured right)

  • Cut or mow annual grass down to a maximum height of 4 inches.

  • Trim tree canopies regularly to keep their branches a minimum of 10 feet from other trees/clusters of trees.

    ** For larger properties, consider areas outside of Zone Two as a third zone to address. Continue reducing ladder fuels, managing fuels, hardening structures, and properly storing combustible materials.

Home Hardening

What is a Hardened Home?

Construction materials and the quality of the defensible space surrounding it are what give a home the best chance to survive a wildland fire. Embers from a wildland fire will find the weak link in your home’s fire protection scheme and gain the upper hand because of a small, overlooked or seemingly inconsequential factor. However, there are measures you can take to safeguard your home from wildland fire. While you may not be able to accomplish all the measures listed below, each will increase your home’s, and possibly your family’s, safety and survival during a wildland fire.

ROOFS

Roofs are the most vulnerable surface where embers land because they can lodge and start a fire. Roof valleys, open ends of barrel tiles, and rain gutters are all points of entry.

EAVES

Embers can gather under open eaves and ignite exposed wood or other combustible material.

VENTS

Embers can enter the attic or other concealed spaces and ignite combustible materials. Vents in eaves and cornices are particularly vulnerable, as are any unscreened vents.

WALLS and FENCING

Combustible siding or other combustible or overlapping materials provide surfaces or crevices for embers to nestle and ignite. Combustible fencing can become engulfed and if attached to the home’s sidings can carry the fire right to the home.

WINDOWS and DOORS

Embers can enter gaps in doors, including garage doors. Plants or combustible storage near windows can be ignited from embers and generate heat that can break windows and/ or melt combustible frames

Landscaping

Watch Out for Exotic Vegetation

Non-native trees, such as ironwood (pictured right), constantly drop needles, leaves, branches, and other debris, so it’s best to stay on top of removing them from the ground before the pile becomes a major project. Consider reforesting these areas with native trees that don’t drop large amounts of debris.

Invasive grasses such as guinea and fountain grass grow rapidly when unmanaged and can dry out very quickly, creating a major fire hazard. Weed them often and consider replanting with low-lying, drought-tolerant, native ground cover.

Xeriscaping - Hawaiʻi Style

Creating a wildfire-resiliant home does not necessarily mean eliminating the presence of greenery on your property. You can still landscape around your home to make it fire-safe without compromising beauty and aesthetics. By planting native, drought-tolerant plants (xeriscaping) around your home, you can: 

  • Protect your home from wildland fire ignition and spread

  • Beautify your property

  • Perpetuate an important natural and cultural resource

  • Decrease the maintenance needs of your landscaping

For the drier areas of Hawai'ʻi, consider that native dryland plants are specially adapted to local conditions and require less upkeep, water, and fire maintenance, saving you a great deal of time, money, and resources. Non-native, lush plants often drop hazardous debris and can become fire-prone in drought conditions.

Tips for Firewise Landscaping

Right Tree

Tree Selection: Choose the right plants and trees for your yard.

  • The right trees can help buffer against a fire rather than being fire hazards.

  • Fires are fueled by dried grasses, woody debris, and dried leaves.

  • Use native and canoe plants that are specially adapted to local conditions and require less water to keep green.

  • When planting a seedling, ensure it has space to mature and grow.

  • Avoid invasive fire-promoting plants and trees like paperbark tea tree, formosan koa, and lantana.

Check out the Weed Fire Risk Assessment for Hawai‘i to determine which plants to exclude or remove from your yard. Plant Pono & SelecTree (click on “Search Pacific Islands”) can help you find the best trees for your yard and conditions.

Right Place

Site selection: Choose the right place for trees in your yard.

  • Allow for space between the tree canopy and your home. Branches should not touch the home.

  • Create a “fire-free” area within 5 feet of your home using gravel, cinder, etc., or well-hydrated plants.

  • Keep maximum distance between tree clusters/canopies to reduce the risk of wildfire spreading between vegetation.

Right Care

  • Regularly remove dried grasses, woody debris, and dried leaves.

  • Regularly trim branches away from your home and other trees.

  • Pruning to allow light and air between branches can promote tree health and resilience to pests.

  • Keep plants and trees well-hydrated and healthy. Native and drought-resistant plants tend to require less water and upkeep.

ROOF

Your roof is the most vulnerable part of your home because it can easily catch fire from windblown embers. Homes with wood-shake or shingle roofs are at high risk of being destroyed during a wildland fire.

Build your roof or re-roof with fire-resistant materials such as composition, metal, or tile. Block any spaces between the roof decking and covering to prevent ember intrusion.

Clear pine needles, leaves, and other debris from your roof and gutters.

Cut any tree branches within ten feet of your roof.

CHIMNEY

Cover your chimney and stovepipe outlets with a non-flammable screen of 1⁄4-inch wire mesh or smaller to prevent embers from escaping and igniting a fire.

Make sure that your chimney is at least 10 feet away from any tree branches.

VENTS

Vents on homes are particularly vulnerable to flying embers.

All vent openings should be covered with 1⁄8-inch or smaller metal mesh. Do not use fiberglass or plastic mesh because they can melt and burn.

Attic vents in eaves or cornices should be baffled or otherwise protected to prevent ember intrusion (mesh is not enough).

NON-COMBUSTIBLE ENCLOSED EAVES

Box in eaves with non-combustible materials to prevent accumulation of embers.

RAINGUTTERS

Screen or enclose rain gutters to prevent accumulation of plant debris.

WALLS

Wood products, such as boards, panels, or shingles, are common siding materials. However, they are combustible and not good choices for fire-prone areas.

Build or remodel with fire-resistant building materials, such as plaster, cement, masonry, or stucco.

Be sure to extend materials from the foundation to the roof.

WINDOWS

Heat from a wildland fire can cause windows to break even before the home ignites. This allows burning embers to enter and start internal fires. Single-pane and large windows are particularly vulnerable.

Install dual-paned windows with the exterior pane of tempered glass to reduce the chance of breakage in a fire.

Limit the size and number of windows in your home that face large areas of vegetation.

DECK or PATIO COVER

Use heavy timber or non-flammable construction material for decks.

Enclose the underside of balconies and decks with fire-resistant materials to prevent embers from blowing underneath.

Keep your deck clear of combustible items, such as baskets, dried flower arrangements, and other debris.

The decking surface must be ignition-resistant if it’s within 10 feet of the home.

INSIDE

Keep working fire extinguishers on hand. Install smoke alarms on each level of your home and near bedrooms. Test them monthly and change the batteries twice a year.

NON-COMBUSTIBLE FENCING

Make sure to use noncombustible fencing to protect your home during a wildland fire.

ADDRESS

Make sure your address is clearly visible from the road.

GARAGE

Have a fire extinguisher and tools such as a shovel, rake, bucket and hoe available for fire emergencies. Install a solid door with self-closing hinges between living areas and the garage. Install weather stripping around and under door to prevent ember intrusion. Store all combustibles and flammable liquids away from ignition sources.

WATER SUPPLY

Have multiple garden hoses that are long enough to reach any area of your home and other structures on your property.

If you have a pool or well, consider a pump.

HOME SITE and YARD

Ensure you have at least a 100-foot radius of thinned, well-maintained, or cleared vegetation around your home. Note that even more clearance may be needed for homes in severe hazard areas. This means looking past what you own to determine the impact a common slope or neighbors’ yard will have on your property during a wildland fire.

Cut dry weeds and grass before noon when temperatures are cooler to reduce the chance of sparking a fire.

Landscape with fire-resistant plants that have a high moisture content and are low-growing.

Keep woodpiles, propane tanks, and combustible materials away from your home and other structures such as garages, barns, and sheds.

Ensure that trees are far away from power lines.

DRIVEWAYS and ACCESS ROADS

Driveways should be designed to allow fire and emergency vehicles and equipment to reach your house.

Access roads should have a minimum 10-foot clearance on either side of the traveled section of the roadway and should allow for two-way traffic.

Ensure that all gates open inward and are wide enough to accommodate emergency equipment.

Trim trees and shrubs overhanging the road to a minimum of 13 1⁄2 feet to allow emergency vehicles to pass.