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Structure Hardening for Embers

All structures MUST be hardened for ember exposures.

Research and experience from past WUI fires shows that a majority of structures are ignited by embers. The widespread and unpredictable nature of ember showers means that all structures need to be protected against ember ignitions.

  • Ember exposures cannot be eliminated or reliably reduced.
  • Embers can arrive miles ahead of the wildfire front and cause ignition to homes and property.
  • A single vulnerability can result in destroyed structures.
  • To reduce ember ignitions of homes, ADUs, and other structures of interest, vulnerabilities on these structures need to be fully mitigated.

HMM recommends addressing all vulnerabilities unique to each structure. Forty vulnerabilities to ember ignition, and their mitigating actions, have been identified in Table A. Steps should be taken to further mitigate any additional vulnerabilities that may be identified on individual structures.


Link/expand to Table A

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Created July 6, 2023, Updated August 22, 2023