Your house is one of the (if not THE) most valuable thing that you own. So, it makes sense that during wildfire season, you want to do everything you can to keep your home and your property safe.
Scientists at the Insurance Institute for Business & Home Safety (IBHS) have found that the ignitability of wildland urban interface (WUI) homes are based on the design, exterior building materials, and proximity to burning objects ignited by firebrands. While you can't avoid the disaster caused by wildfires, you can limit the damage done by eliminating the amount of fuel that brings flames and embers dangerously close to your property.
By now, you have the necessary tools to make your home's landscape less fire-prone and what structural materials are less vulnerable to wildfires. Now, it's time to focus on your defensible space.
According to the IBHS, your "defensible space" is comprised of three zones. Here's a definition of each one and what experts recommend for each zone to prepare your home for wildfire season.
Zone 1: areas that are 0-5 feet around the house and under the entire deck.
This zone is the closest to your home, so the objective of all zone 1 work is to reduce the chance that ignition will come into contact with the building. If it's possible, IBHS and Federal Emergency Management Agency (FEMA) recommends that you:
- Install hard surfaces in this zone (like a concrete walkway) or use noncombustible mulch products (like rock mulch).
- Use low-growing, non-woody plants, and keep your lawn watered.
- Remove dead plant material and combustible materials on the roof, windows, gutters, vents, and within 30 feet of the home.
- Trim tree branches.
Zone 2: areas that are 5-30 feet away from the house (or to the property line).
The objective for zone 2 should be vegetation management and spacing of plants, to prevent the fire from climbing into the upper portions of trees and shrubs and to keep the fire from burning directly to your home. IBHS and FEMA suggest the following:
- Prune and remove dead and dying branches from individual and well-spaced clumps or trees and shrubs.
- Place woodpiles at least 30 feet from the building and store the wood in a vegetation-free zone such as a graveled area.
- Create groupings of vegetation to form a discontinuous path, which makes it difficult for the fire to burn directly to your home.
- Maintain trees by keeping a minimum horizontal spacing of 10 feet between crowns, with the distance increasing with increasing slope. Prune limbs and branches to a height of up to 15 feet. For shorter trees, pruning should not exceed 1/3 of the tree height.
Zone 3: areas that are 30-100 feet away from the house (or to the property line).
This zone is the farthest away from your home, and all upkeep here is meant to slow down and reduce the energy of the wildfire—slowing its advance to your house. "The rate of spread and flame length of a wildfire is affected by slope," states IBHS. "A steeper slope will result in a faster-moving fire with longer flame lengths."
Here's what the experts say to do:
- Remove dead plant material and tree branches from vegetation on a regular maintenance schedule.
- Get rid of low tree branches and nearby shrubs.
- Keep or plant trees at a minimum horizontal spacing of 10 feet between edges. From the perspective of tree health, branch removal should not exceed 1/3 of the tree height.
Idaho Firewise is a non-profit organization that develops and promotes statewide wildfire education for those who live in or visit Idaho. To learn more about wildfire prevention and protection, visit www.idahofirewise.org.