Protect Your Property Using the Home Ignition Zone
Throughout October and these first few days of November, California has been battling wildfires. And the parts of the state that haven’t been on fire have been under wildfire watch. After the town of Paradise was decimated by the Camp fire last year, many people in Northern California are more aware than ever of the dangers that fire presents.
The Camp fire also taught us that not just rural grass lands and forests are subject to the damage of wildfires. Whole towns can be taken down by a wildfire in mere hours. No matter if you live in the suburbs or on property it is important to make sure that your home is prepared for a wildfire.
Home Ignition Zone
In the late 1990’s Jack Cohen, a retired fire scientist from the USDA Forest Service created a concept called the home ignition zone. NFPA states that Cohen developed this after he did, “experimental research into how homes ignite due to the effects of radiant heat”.
The home ignition zone is made up of three separate zones; immediate, intermediate, and extended. Read more below about each of these zones.
NFPA classifies the immediate zone as the home itself and “0-5’ from the further attached exterior point of the home”. This is the most important zone to take care because it is the most vulnerable to embers.
When preparing the immediate zone for fire, NFPA recommends that you:
- Clean roofs and gutters of dead leaves, debris and pine needles that could catch embers.
- Replace or repair any loose or missing shingles or roof tiles to prevent ember penetration.
- Reduce embers that could pass through vents in the eaves by installing 1/8 inch metal mesh screening.
- Clean debris from exterior attic vents and install 1/8 inch metal mesh screening to reduce embers.
- Repair or replace damaged or loose window screens and any broken window screen or box-in areas below patios and decks with wire mesh to prevent debris and combustible materials from accumulating.
- Move any flammable material away from wall exteriors – mulch, flammable plants, leaves and needles, firewood piles – anything that can burn. Remove anything stored underneath decks or porches.
NFPA classifies the intermediate zone as “5-30’ from the furthest exterior point of the home”. This mainly focuses on landscaping and how proper landscaping can help create a break “that can help influence and decrease fire behavior”.
When preparing the intermediate zone for fire, NFPA recommends that you:
- Clear vegetation from under large stationary propane tanks.
- Create fuel breaks with driveways, walkways/paths, patios, and decks.
- Keep lawns and native grasses mowed to a height of four inches.
- Remove ladder fuels (vegetation under trees) so a surface fire cannot reach the crowns. Prune trees up to six to ten feet from the ground; for shorter trees do not
NFPA classifies the extended zone as “30-100 feet, out to 200 feet.” This area’s goal is to “not interrupt fire but to interrupt fire’s path and keep flames smaller and on the ground”.
When preparing the extended zone for fire, NFPA recommends that you:
- Remove dead plant and tree material.
- Dispose of heavy accumulations of ground litter/debris.
- Remove small conifers growing between mature trees.
- Remove vegetation adjacent to storage sheds or other outbuildings within this area.
- Trees 30 to 60 feet from the home should have at least 12 feet between canopy tops.*
- Trees 60 to 100 feet from the home should have at least 6 feet between canopy tops.*
*The distances listed from crown spacing are suggested based on NFPA 1144. However, the crown spacing needed to reduce/prevent crown fire potential could be significantly greater due to slope, the species of trees involved and other site specific conditions. Check with your local forestry professional to get advice on what is appropriate for your property.
For more information about wildfires, check out our previous blog post – The Threat of Wildfires.
-The IFS Team