Protecting Your Business from Wildfire – All Fire Hazard Severity Zone Areas

Recommendations: All Fire Hazard Severity Zone Areas

A Vegetation Management Plan should be submitted for review and approval.

Building-Related Properties and Recommendations

Roof coverings should have a Class A fire rating based on testing to ASTM E 108, UL 790 or FM 4470.

Any openings between the roof covering and roof deck at the roof edge and/or ridge should be plugged using a noncombustible material (i.e., bird-stopped).

Projections from sloped or flat roofs (e.g., a dormer or a wall of a taller portion of the building) should be clad with a noncombustible or ignition-resistant material.

Exposed roof valley flashings should be corrosion-resistant metal and installed over a minimum 36-in. wide underlayment consisting of one layer of No. 72 ASTM cap sheet running the full length of the valley.

Gutters and downspouts should be of noncombustible materials. Typical aluminum gutters and downspouts are acceptable. The gutter should incorporate an integral metal flashing at the roof edge, or a separate angle flashing should be used at the roof edge. Clearing debris from gutters should be incorporated into a routine maintenance and upkeep plan for the building(s) in the development.

Eave construction should incorporate a soffited design using a horizontal return from roof edge to the exterior wall.

Soffit vent openings: Noncombustible, corrosion-resistant screening with a mesh size no greater than 1/8 in. should be used to cover the attic, sub-floor and other vent openings on the wall. When vent openings are integrated within the soffit material, an individual vent opening should not exceed 1/8-in. diameter or 0.05 sq in. Vents designed for use in wildland urban interface areas that have been accepted for use by the AHJ should be allowed for use.

Operational windows should have screens covering those sections that can open.

Vehicle access (garage) doors should be weather-sealed around the perimeter to minimize entry of embers.

Storage of combustible materials: Combustible materials should not be stored under attached decks.

Deck boards: Solid wood, plastic, or wood-plastic composite deck boards (all are combustible products) should comply with the requirements of Chapter 7A, California Building Code. A listing of compliant products can be found at the California Office of the State Fire Marshal Building Materials Listing Program website at searchcotest.php. Select category option “8110 – Decking for Wildland Urban Interface (W.U.I.).”

Spark arrestors with 1/2 in. mesh screening should be installed at the outlet of all chimneys.

Interior fire protection system should include monitored fire sprinkler system (preferred), or monitored smoke and/or heat detectors.

The following relate to control of combustible materials on the parcel/surrounding area:

Defensible space should be created and maintained as previously outlined and as provided in the Vegetation Management Plan.

Signage should be made from a noncombustible material. Street numbers should be at least 4-in. high, reflective, applied on a contrasting background, at each driveway entrance, and be visible from both directions of travel.

Firewood storage and liquefied propane (LP) gas containers should be at least 30 ft from the building. The firewood should not serve as ladder fuel into nearby vegetation. LP gas containers should have a 10-ft noncombustible zone extending out from the outside edge of the container. Alternatively, the container can be surrounded by a CMU block wall, with wall height equaling the container height. The wall should provide ventilation at the bottom to reduce the accumulation of LP gas should a leak occur.

Entrances and driveways should be at least 12-ft wide with at least 13.5 ft of vertical clearance. The angle of approach and departure should be designed to allow for emergency vehicle access without damaging the equipment when entering or leaving the driveway.

If property is gated, the gate should open inward and have an entrance at least 2 ft wider than the driveway. Any gate should be located at least 30 ft from a roadway intersection. If secured, the gate should have a key box or lock of a type approved by the local AHJ

Flammable liquids: Small quantities of combustible and flammable liquids stored outside should be located in UL or FM Approved fire rated cabinets and labeled with appropriate signage.

Fire hydrants should be located within 250-500 ft, or as approved by the fire authority having jurisdiction (FAHJ), of the building connected to a reliable public or private water supply.

Setback of buildings and structures: Buildings and structures should be set back a minimum of 30 ft from any property line adjacent to a national forest, state park, open space preserve or other protected wildland.

Planned landscaping planted adjacent to the building(s) should be irrigated.