Appendix B: Long-term actions
Some actions are more complex and expensive, may require expert help and take several years to implement.
Make an overview sketch of the features of your lot and house including slope, trees, shrub, decks. Next, make sketches of each side of your house, with special attention to the side that a fire is most likely to approach it. Ask the local fire authority to visit and make suggestions about how to improve your analysis.
Roof and roofing materials (fire barrier and roof deck)
Perhaps the greatest threat to your house is a combustible roof covering or openings in the coverings. If you have an untreated shake roof, your odds are poor for survival in a major wildfire. Check to see what your roofing type is (roofs are rated A, B, or C, depending on the roofing material and overall construction). If in doubt, ask your local fire authority or check your house construction permit on file. Don't assume that a tile roof is safe if it has unstopped openings at the edges or has valleys with combustibles. This can be as hazardous as an untreated shake roof since the fire can bypass the covering. If you are considering changing a shake roof to a heavier roofing material, such as tile, get advice about the possible need to reinforce your roof for the added weight. Qualified roofers should be able to provide this advice.
Nearby fences and gates
In the 2003 southern California fires, there was clear evidence that wooden fences close to structures can lead to damage. This is even more hazardous when a fence has a combustible gate attached to the side of the house, which is typical construction. The fence/gate combination is a collection point for combustibles (trash, leaves, etc) as well as brands. The garage in the photo caught on fire and the house was lost.
For houses with close spacing, wooden fences can easily ignite under some conditions. There are two particular concerns: (1) wooden gates used for closure between fences and houses, and (2) combustibles against fences. For the former, we recommend that the gate be non-combustible. For the latter, there are several actions, but perhaps the most important is to create a gap of about one inch at the bottom end of the fence boards. This will reduce the potential of decay of the bottom ends of the boards, making them much more resistant to ignition. The other action is to keep combustibles away from fences, especially the type that can collect at the base.
Ancillary structures (decks, porches, landings)
The hazard presented by these structures cannot be over-estimated. In most cases, embers can lodge into areas (seams, gaps) and initiate a destructive fire. The intersection between horizontal and vertical surfaces is especially susceptible to fire and very difficult to make fire safe. The variety of construction of existing houses and ancillary structures make remediation very difficult. However, it is very helpful to keep gaps and corners clean of combustibles, including trash and leaves, to reduce the hazard. One very positive action that can be taken is to remove any combustibles from beneath these structures and screen the under areas to prevent brands from entering. The screening should have a maximum of 1/4-inch openings, but smaller (1/8-inch) is much better. It is also helpful to add ground coverings to minimize the growth of vegetation
Move your firewood as far from the house as possible. Many people store firewood close to their houses for convenience and to shelter the wood from rain. Unfortunately, a typical wood pile is one of the greatest hazards to a structure. You should store your firewood at least 20 feet away from your house. If there is a concern about protection from rain, then fabricate a cover.
If you have a down slope from your house with annual grasses/weeds, think about a low-form, fire-resistant, drought-resistant plant. This may take a few years to fully develop (with watering in the first year or so), but it can serve as a significant barrier to spread of fire. Flashy fuels, such as grasses are one of the greatest hazards in California.
Trees don't have to be a problem as long as they're some distance from the house, say 6 feet of the closest branches, so trim back what you can, but begin a removal/replacement program. A good choice for a tree in California is a deciduous one, especially on the south side of your house. It will provide shade in the summer and lose its leaves before the fire weather. Also, as pointed out in the Quick-fix, don't have large bushes under any trees.
Spacing between shrubbery, with materials like grass or gravel will provide a fire break. Create green islands instead of large clumps of vegetation. The gaps should be greater as you approach the house.
Create radiation shields and wind breaks if your location is on a rim. This can be done with trees, hedges, or non-flammable walls.
These are your view to the outside world and a major point of fire's entry. Fire can enter through high radiant energy that fractures the glass (glass will expand much more than the frames and break), the impact of wind-blown flaming brands (which can be very large), or flames impinging on the glass (and the radiation from the flames) to cause fracture.
The first step is to remove any combustibles (including large plants) from beneath first-floor windows. The safest approach is to have low-form ground-cover plants under windows.
Next, where there are combustibles such as decks, the only reasonable solution is to protect the windows or modify them. An old solution is to use exterior shutters to act as a barrier. A relatively modern approach is to use tempered glass in such windows (or sliding doors). This has been required in new construction for any glass within 18 in. of a walking surface since 1972.
In the relatively mild climate of California, there are many existing older homes with single pane glass. The highest priority is for the first floor, especially on the side of the house from which a fire would most logically approach.
These openings in houses serve several purposes: removal of excess moisture and reduction of roof and attic temperatures. There are many types of vents that are located in soffits, roofs ("eyebrow" or "through-roof" vents), tops of roofs (ridge vents), top ends of walls (gable vents), and crawl spaces. Of these, the soffit vents are most vulnerable to fire. We recommend the following for soffit vents:
First, do not permanently block these vents without having additional adequate vents added. There is a minimum venting required by building code and this is barely adequate for most houses. Reducing the venting can lead to serious potential decay damage from accumulation of condensation in the attic area.
Consider advice from a contractor about your options. If you are considering replacing your roofing material, then the roof-type vents should be seriously considered. Gable vents are also a good retrofit option for some walls.
Above all, be sure that you do not have large plants at the ground line directly below soffit vents. A poorly maintained bush about 3 feet high can burn with flames more than high enough to reach your soffits and go through the vents
It has been found that the commonly used soffit materials are totally inadequate in preventing a fire from entering into the eaves. Your soffits should be either a noncombustible material (such as a fiber cement product) or 3/4-inch plywood. The plywood should have tongue and groove connections to prevent fire entry through the joints.
Siding (cladding) of the house can be a problem depending on the likelihood of ignition, and what is above the siding. If your type of siding is combustible, which most are other than stucco and cement, it can act as a "fire ladder" and move the fire vertically into the eaves and potentially through the soffit material or vents. However, even combustible siding may not be a fire hazard if:
a. There are no combustibles at the base (such as plants, decks, etc).
b. A non-combustible material separates the siding (about 12 inches) from combustibles at the base.
c. The material does not have openings for brands to enter. This is particularly important for lapped siding (both horizontal and vertical), and for inside corners of buildings.
Stucco cladding walls can be OK as long as the stucco is thick enough (about 7/8 inch) and has sheathing beneath it (the traditional 3-coat stucco is this thickness). The horizontal lapped type of cement cladding may be non-hazardous if the laps are tight, however, any lapped material, if warped sufficiently to provide fire entry may permit fire to enter into the area of the sheathing.
The ability of firefighters to protect your house is only effective if they can reach it with their equipment and have adequate space to operate in. You should have your local fire authority inspect for all of the infrastructural needs for them to defend your house.