Embers Destroy 90% of Buildings During a Wildfire Attack. Immediate DIY Home Preparation Actions for Europeans in Wildfire Risk Areas.
A quick DIY guide for Europeans (and others) to protect homes and buildings against wildfire attack from best practices around the world.
For those families who have time to prepare their homes, I have highlighted below some immediate, simple and effective actions that a homeowner can take to protect one’s home and community. These actions are based off best practices from Australia and the U.S.
90% of homes and buildings are destroyed during a wildfire attack by embers or firebrands, which can travel up to 40km from the fire front. These embers can enter gaps as small as 2mm or 0.0787”, igniting the home from the inside out. A critical step is for homeowner’s is to identify any gaps, vents and any openings that could allow embers to penetrate and either block them or install an ember resistant mesh.
As mentioned in my first article, the most important thing to do is to Prepare against the threat of Wildfire. Preparing for wildfires should consider the two zones that you are trying to protect:
· Zone 0 – Your Building through Home Hardening
· Zone 1 – Your Property through creating a Defensible Space
The below summary of best practices for Home Hardening and Defensible Space are quick DIY actions that should see immediate results and will hopefully help protect people’s homes and communities. Following these practices will not guarantee your home will not be damaged but they will improve the likelihood of your home being affected. We believe protecting against Wildfire Threat can save you and your family precious time that can allow you to either evacuate safely or protect your home.
Zone 0 Home Hardening (Last line of defense to protect your home)
Home Hardening is to modify the building materials and design features of the home for wildfires against the number one threat from Wildfires – Embers and then Radiant Heat and Direct Flame.
It is critical when you home harden, that you use the correct products which will survive the environment and wildfire attack. There is no silver bullet, so its best to create a barrier approach with a combination of products and solutions. Where Mesh, Screens, etc is stated, it is best to use the following:
- Material: When noncombustible, corrosion resistant metal is referenced, this must be Stainless Steel. While Hot Dipped Galvanized may last for the immediate purpose, in the long-term it is not corrosion resistant and therefore not built to last the changing environment and Wildfires.
- Mesh sizing: The current IWUIC code state a maximum of 1/8” (0.125″) or 3.175mm (which is often referred to as Rodent protection) with fire authorities and best practices recommending 1/16” (0.063″) or 1.5mm opening. Australian Standards suggest a mesh opening size of less than 2mm (0.078”) to cover a 2mm (0.078”) gap as research from the US showed embers can enter a 2mm (0.078”) gap.
A simple and effective Home Hardening Low Cost Retrofit List is offered by the Office of State Fire Marshall (OSFM) at CAL FIRE (California Department of Forestry and Fire Prevention). These best practices are separate from the California Building Code and are recommended in California for retrofit purposes. There is much cross-over from the Australian Bushfire Authorities, IBHS, etc for best practices. I have added Timing of Actions to this list, so homeowners can see what immediate Actions can be performed with little cost.
Zone 1 Defensible Space
Defensible Space is the buffer you create by removing dead plants, grass and weeds and other combustible materials from around your home. This buffer helps to keep the fire threats of Direct Flame and Radiant Heat away from your home. While these threats contribute only 10% of Building fires during Wildfires, the small amount of effort to create the Defensible Space is strongly encouraged. Especially when creating further barriers to prevent spot fires and the creation of more embers.
1. Clean gutters, decks, roofs and the base of walls to avoid the accumulation of fallen leaves, needles and other flammable materials
2. Create and maintain a 0–5 ft non-combustible zone around a building, including the entire footprint of an attached deck
– Remove vegetation or non-combustible material that are within 5 feet of windows, doors and siding
– Add non-combustible material like dirt, gravel or stones to the 0-5 ft but not wood mulch
3. Remove all dead or dying grass, plants, shrubs, trees, branches, leaves, weeds, and pine needles within 30 feet of all structures or to the property line.
4. Remove any wood stacked near your house
5. Talk with your neighbors and understand what they are doing to prepare – often the ignition source in a wildfire is the building next door and if they are not prepared then this may impact on you building
About the Author
My family business, Stainless Steel Wire and Mesh (SSWM) has been innovating Bushfire Mesh for over 12 years in the Australian Market and I have been localizing it to the U.S. Market in recent years. I have spent much of the last few years reviewing and testing product to Wildfire Building Codes from Australia (AS 3959 – Constructions of Buildings in Bushfire Prone Areas), United States (IWUIC, International Wildland Urban Interface Code), California (Chapter 7A, California Building Code 2019), and best practices from CSIRO, IBHS, CAL Fire, NFPA / Fire Wise, FEMA, etc.
Some great resources for further information on best practices and wildfire preparation, please refer to the following links:
Insurance Institute for Business & Home Safety (IBHS) – Wildfire Prepared Home
CAL FIRE Office of State Fire Marshall (OFSM) – Low Cost Retrofit List
NFPA / FireWise – Preparing Homes for Wildfires
Wildfire Risk to Communities – Home Hardening
California FireSafe Council – Home Hardening
CSIRO – Bushfire Best Practices Guide
Country Fire Authority (CFA) / Victorian Building Authority – A guide to retrofit your home for better protection from a bushfire