Wildfire resilience field guide
Home Hardening vs Defensible Space: what is the difference?
Home hardening changes the building. Defensible space changes the fuels and combustible conditions around it. The strongest wildfire strategy uses both.
Core distinction
Structure resistance vs surrounding fuel management.
California wildfire guidance treats home hardening and defensible space as complementary but different actions.
Retrofitting or constructing the building with features and materials intended to reduce vulnerability to embers, radiant heat and direct flame contact.
Creating and maintaining a buffer between structures and surrounding vegetation or combustible material to reduce fire intensity near the building and improve access.
How homes ignite
Embers, direct flame and radiant heat are different pathways.
CAL FIRE identifies flying embers, direct flame contact and radiant heat as three principal ways homes can be exposed during wildfire. Home hardening primarily addresses the building’s ability to resist those exposures, while defensible space reduces nearby fuel sources and fire intensity.
Examples
Different work, same resilience objective.
Ember-resistant vents, roof and siding upgrades, enclosed eaves, improved windows and reducing combustible attachments.
Removing dead vegetation, separating fuels, managing ladder fuels and reducing combustible material immediately around the structure.
Use the tools
Turn the concept into measurable planning.
Source
California wildfire-preparedness guidance.
CAL FIRE — Ready, Set, Go! Wildfire Action Plan ↗
Published 21 September 2026.