Building and Living in California’s Wildland Urban Interface Presented by CAL FIRE California...

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Building and Living in Building and Living in California’s California’s Wildland Urban Interface Wildland Urban Interface Presented by Presented by CAL FIRE CAL FIRE California Department of Forestry and Fire Protect California Department of Forestry and Fire Protect State Fire Marshal State Fire Marshal

Transcript of Building and Living in California’s Wildland Urban Interface Presented by CAL FIRE California...

Building and Living in California’sBuilding and Living in California’sWildland Urban InterfaceWildland Urban Interface

Presented byPresented by

CAL FIRECAL FIRECalifornia Department of Forestry and Fire ProtectionCalifornia Department of Forestry and Fire Protection

State Fire MarshalState Fire Marshal

California has one of the most severe California has one of the most severe wildland fire problems in the world.wildland fire problems in the world.

• Population Population (over 5 million in fire hazard areas)(over 5 million in fire hazard areas)

• VegetationVegetation

• Topography Topography

• ClimateClimate

Fires have burned in Californiathroughout its history.It is a part of nature.

Homes are burned, Homes are burned, lives lost, businesses ruined.lives lost, businesses ruined.

Fire Siege 2003

Conflagration FiresConflagration Fires

Most high fire losses Most high fire losses are during hot, windy are during hot, windy days or nights when days or nights when flames spread rapidly.flames spread rapidly.

Winds blow embers Winds blow embers sometimes miles sometimes miles from the main fire. from the main fire.

There are not enough There are not enough firefighters to protect all the firefighters to protect all the Structures threatened, and resources Structures threatened, and resources become overwhelmed.become overwhelmed.

Can we afford the millions of dollarsCan we afford the millions of dollarsspent every year to protect homes spent every year to protect homes and property from wildfires?and property from wildfires?

Is there a way to prevent the devastationIs there a way to prevent the devastationand prepare for the inevitable?and prepare for the inevitable?

Who is in the fire prone Who is in the fire prone areas of California?areas of California?

This map is a This map is a draft and can be draft and can be

expected to change expected to change before the maps are before the maps are

completed. completed.

State Responsibility Area State Responsibility Area (SRA) Maps:(SRA) Maps:

• Released to CAL FIRE Released to CAL FIRE units May 2007units May 2007• County public hearing County public hearing process process • Moderate, high, and veryModerate, high, and very high zoneshigh zones• Final maps completed byFinal maps completed by January 2008January 2008

Fire Hazard Fire Hazard Severity Zones Severity Zones

SRA FHSZSRA FHSZDraft County MapDraft County Map

Moderate ZonesModerate ZonesHigh ZonesHigh ZonesVery High ZonesVery High Zones

Local Responsibility Area Local Responsibility Area (LRA) (LRA) MapsMaps

• Sent to local agencies having jurisdictionSent to local agencies having jurisdiction after SRA Maps are approvedafter SRA Maps are approved

• Only Very High FHSZ will be mappedOnly Very High FHSZ will be mapped

• Local Government HearingsLocal Government Hearings

• Final Maps approximately January 2009Final Maps approximately January 2009

Example of Example of how a local how a local Fire Hazard Fire Hazard Severity Severity Map may be Map may be used with a used with a parcel layer.parcel layer.

This helps This helps Building and Building and Fire Officials Fire Officials determine determine what what provisions provisions would apply would apply to a builder.to a builder.

Napa CountyFire Riskby Parcel

LegendNapa County Fire Risk

County Parcels

Low

Med

High

0 105

Scale in Miles

0 10.5

Scale in Miles

Inset Map to Left:

Circle Oaks housing division near Lake Berryessa

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Direct flame impingement Direct flame impingement from nearby vegetation, from nearby vegetation,

debris, or other combustible materialsdebris, or other combustible materials

Radiant heat Radiant heat from dense vegetation, adjacent tofrom dense vegetation, adjacent to structure/decks. Cause combustibles to heat up, thenstructure/decks. Cause combustibles to heat up, then ignite.ignite.

Airborne burning embersAirborne burning embers enter a structure through enter a structure through

small openings or lodge/collect in areas where the small openings or lodge/collect in areas where the

embers smolder and are fanned by winds, then embers smolder and are fanned by winds, then

combustible material ignites, sometimes hours after combustible material ignites, sometimes hours after

the fire has passed.the fire has passed.

Why Buildings Burn in theWhy Buildings Burn in theWildland Urban InterfaceWildland Urban Interface

From: Landscape and Building Design for Bushfire Areas. Ramsay & Rudolph, CSIRO

Building exposed to the Building exposed to the main flame frontmain flame front of a wildfire for a relatively of a wildfire for a relatively short period of time – 5 to 10 minutes. (Direct Flame Impingement)short period of time – 5 to 10 minutes. (Direct Flame Impingement)

Wildfire ThreatsWildfire ThreatsTo BuildingsTo Buildings

Building will be exposed to pre- and post- fire Building will be exposed to pre- and post- fire flying embersflying embers much much longer, especially during wind driven fires. (Airborne Burning longer, especially during wind driven fires. (Airborne Burning Embers)Embers)

If one building starts to burn, it becomes a threat to others.If one building starts to burn, it becomes a threat to others.(Radiant Heat)(Radiant Heat)

Applies to:Applies to: New Construction in all of the SRA New Construction in all of the SRA

New Construction in Very High Fire New Construction in Very High Fire Hazard Severity Zones in Local Hazard Severity Zones in Local Jurisdiction Jurisdiction

((Buildings in Federal Lands: Check with Local Jurisdiction)Buildings in Federal Lands: Check with Local Jurisdiction)

New Wildland Urban Interface New Wildland Urban Interface Building Code StandardsBuilding Code Standards

Chapter 7AChapter 7ACalifornia Building CodeCalifornia Building Code

Window Testing

Wall Testing

Ignition Resistive Materials Testing

Building Standards Focus on Building Standards Focus on Eliminating Ember IgnitionsEliminating Ember Ignitions

Phase I Phase I Now in Effect Now in Effect

RoofsRoofsClass A for all VHFHSZ, Class B for HFHSZ and Class C Class A for all VHFHSZ, Class B for HFHSZ and Class C for MFHSZ in SRA)for MFHSZ in SRA)

Roof GuttersRoof GuttersProvided with the means to prevent the accumulation of Provided with the means to prevent the accumulation of debrisdebris

Vents Vents ““Resistant to intrusion of flame and embers” or non-Resistant to intrusion of flame and embers” or non-combustible ¼” (6 mm) mesh screen combustible ¼” (6 mm) mesh screen maximummaximum

Roof and Roof Assemblies

Absence of sustained flaming or glowing combustion of any kind at the conclusion of the 90-min observation period.

From This…. To This….

Changes in Roofs and Roof Assemblies

From This….

To This….

Changes in Roof Gutters

Phase II effective January 1, 2008Phase II effective January 1, 2008

Ignition Resistant Construction:Ignition Resistant Construction:• Exterior sidingExterior siding• Exterior wall ventsExterior wall vents• Exterior doorsExterior doors• Decking surfacesDecking surfaces• Floor projectionsFloor projections• WindowsWindows

Building Standards Focus on Building Standards Focus on Eliminating Ember Ignitions Eliminating Ember Ignitions

Exterior Wall• Absence of flame penetration through the wall

assembly at any time.

• Absence of evidence of glowing combustion on the interior surface of the assembly at the end of the 70-min test.

 Windows• Absence of flame penetration of windows during the test.

 • Absence of structural failure of the Frame or glazing, or gaps or fissures

greater than 0.25 x 6 in. (6 x 150 mm).

• Absence of flaming or glowing combustion of the framing at the conclusion of the 40-min test.

Eaves

•  Absence of flame penetration of the eaves at any time.

•  Absence of structural failure of the eaves subassembly at any time.

• Absence of sustained combustion of any kind at the conclusion of the 40-min test.

DecksPeak heat release rate of less than or equal to 25 kW/ft2 (2.3 kW/m2). Absence of sustained flaming or glowing combustion of any kind at the conclusion of the 40-min observation period. Absence of structural failure of any deck board.

Building StandardsBuilding StandardsANDAND

Defensible SpaceDefensible Space

Public Resources Code (PRC) 4290 and Public Resources Code (PRC) 4290 and 4291 Defensible Space4291 Defensible Space

• Remove dead vegetation 30 feet around the building.Remove dead vegetation 30 feet around the building.

• Modify brush, flammable vegetation, or combustibleModify brush, flammable vegetation, or combustible growth within 100 feet around the building by thinninggrowth within 100 feet around the building by thinning and trimming to minimize a continuous “fuel” path to and trimming to minimize a continuous “fuel” path to the structure.the structure.

• Road standards for fire equipment access. Road standards for fire equipment access. • Standards for signs identifying streets, roads, Standards for signs identifying streets, roads, and buildings.and buildings.• Minimum private water supply reserves for emergency Minimum private water supply reserves for emergency fire use. fire use. • Fuel breaks and greenbelts. Fuel breaks and greenbelts. • Remove portion of any tree that extends within 10 feet of Remove portion of any tree that extends within 10 feet of

the outlet of a chimney or stovepipe. the outlet of a chimney or stovepipe.

Public Resources Code (PRC) 4291Public Resources Code (PRC) 4291

Help firefighters protect homes…Help firefighters protect homes…

100 foot defensible space 100 foot defensible space Wildland Urban Interface Building StandardsWildland Urban Interface Building Standards

It can and will happen again….It can and will happen again….

Thank you to all the stakeholders who Thank you to all the stakeholders who collaborated to write the new codes:collaborated to write the new codes:

Dept. of Housing &Community DevelopmentDept. of Housing &Community DevelopmentCalifornia Building Industry AssociationCalifornia Building Industry AssociationCal-ChiefsCal-ChiefsNorCal Fire Prevention OfficersNorCal Fire Prevention OfficersSoCal Fire Prevention OfficersSoCal Fire Prevention OfficersLeague of California CitiesLeague of California CitiesCalifornia Building Officials AssociationCalifornia Building Officials AssociationUC BerkeleyUC BerkeleyUC Cooperative ExtensionUC Cooperative ExtensionRegional Council of Rural CountiesRegional Council of Rural CountiesPersonal Insurance FederationPersonal Insurance FederationWestern Fire CenterWestern Fire CenterC.C. Lewis and AssociatesC.C. Lewis and Associates

Additional InformationAdditional Information

http://www.fire.ca.gov/wildland.php

http://firecenter.berkeley.edu/toolkit

http://www.firewise.org

http://www.firesafecouncil.org

Questions?Questions?