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Retrofit Guide

ibhs fsm retrofit guide coverDownload the IBHS Wildfire Home Hardening Retrofit Guide for California and Marin.FIRESafe MARIN was awarded a grant by CSAA Insurance Group to develop a custom home hardening education program and guidebook for California Residents. The Retrofit Guide available here for download is courtesy of IBHS, the Insurance Institute for Building and Home Safety, and is the top resource available today for homeowners interested in retrofitting existing homes.


Research and post-fire assessments have shown that property owners can protect their homes and businesses against wildfire by addressing three clear sources of vulnerability: materials and design features used in building the home or business, the landscaping vegetation located immediately adjacent to the home or business, and the general vegetation and other combustible materials and items on the property surrounding the home or business. Each of these sources can be dealt with through maintenance, appropriate choices in building materials, design improvements, and vegetation management. 

Making your home or business and community better able to survive a wildfire is a process that will be well worth the effort. Some projects can be done in a weekend, although it is important to remember that routine maintenance must be part of any long-term plan to reduce the vulnerability of your home or business to wildfire. 

This guide was created specifically for Californians and considers appropriate building styles and construction materials, common topographical features, and other factors. While reducing the vulnerability of your home or business to wildfire begins with you, a community-wide approach to fire protection will be the most effective, so please share this guide with friends and neighbors. This guide will provide information that will help your home or business and your community prepare for and survive a wildfire. 

Reducing the Vulnerability of Your Home or Business: An Overview of this Guide 

Wildfires can be difficult to control. What is controllable is how you prepare your home or business for wildfire before it threatens. Ultimately, the difference between survival and destruction are the steps you take to reduce the opportunity for the initial ignition of your home or business. There is an explicit link between the selected vegetation, its placement and management in the area surrounding a building, often referred to as “defensible space,” and construction materials and building design. Survivability of a building will depend on creating and maintaining an effective defensible space on the property and on careful selection of building materials and construction design features. 

The ignition of a building during a wildfire can occur in one of three ways. These include exposure to wind-blown embers (also known as “firebrands”), direct contact by flames, or a radiant heat exposure (radiant heat is the heat felt standing near a burning object, such as a campfire; but during a wildfire, the heat source could include burning items such as a woodpile, tool shed and/or a large shrub). Of these, exposure to wind-blown embers is considered the most important. Wind-blown embers generated by the burning wildland vegetation, or other burning buildings or structures, can land on or near your home or business and ignite it either directly or indirectly. Examples of a direct ember ignition include ember entry through a vent or open window with subsequent ignition of combustible materials or furnishings inside the building. Direct ignition by embers also can occur through sufficient ember accumulation on combustible materials such as a wood shake roof, on combustible decking, or immediately adjacent to combustible materials such as siding. Examples of an indirect exposure include ember accumulation and ignition of vegetation or other combustible materials (e.g., a woodpile or shed) located near your home or business, with subsequent ignition of a building component by a radiant and/or direct flame contact exposure. With inadequate defensible space, the wildfire could burn directly to your home or business and ignite an exterior component, or break the glass in a window and ultimately burn into the interior of the building. Developing and maintaining an effective defensible space will minimize the chance of this happening. 

Once homes and other structures ignite and burn, they will become a source of embers and threaten other homes and buildings. Depending on building-to-building spacing and topographical features, one wildland fire-to-building ignition can result in additional ignitions by building-to-building fire spread. Building-to-building ignitions can result from embers, direct flame contact and/ or radiant heat exposures. The potential damage from radiant heat will depend on the level and duration of the exposure. The radiant heat exposure from a burning building will be longer than that from a burning shrub. 

This guide provides information for reducing the vulnerability of your home or business to wildfire. Vulnerable parts of a building include the roof, the area immediately adjacent to the building and under any attached deck, vents and other openings on the exterior walls, gutters, decks and siding. Specific details on reducing the vulnerability of your home or business will be provided.

Information courtesy of Insurance Institute for Building & Home Safety (IBHS)

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