Building for fire on the South Coast, ember by ember
Most homes lost in a wildland fire are not lost to flame. The State Fire Marshal puts it at 60 to 90 percent of home ignitions: embers, arriving ahead of the fire and finding a way in.
Two sets of rules. A house can pass one and fail the other.
The building code governs materials and assemblies in hazard zones; your fire district governs vegetation, defensible space, access and water. Your zone, if any, and your district’s rules can be read from the address before anything is drawn.
What changed on January 1, 2026
The wildfire rules left Chapter 7A of the California Building Code for a code of their own: the California Wildland-Urban Interface Code, Title 24, Part 7. It applies in Moderate, High and Very High Fire Hazard Severity Zones, not only the highest.
The maps moved too. In April 2025, new CAL FIRE maps added fire hazard zones inside the City of Santa Barbara, including parts of the Mesa near Cliff Drive and northern San Roque and La Cumbre. A house bought outside a zone may be in one now, and a renovation there is designed to the new rules.
Why this coast
Sundowners, downslope winds off the Santa Ynez Mountains, blow most often in spring, typically starting near sunset. The Tea Fire (November 2008) destroyed 210 homes; the Jesusita Fire (May 2009), 80 more. The Thomas Fire began on December 4, 2017, and burned 281,893 acres before it was contained the following January.
Where embers get in
Post-fire investigation keeps finding it: houses are lost to embers getting in, not to a wall of flame. Specify for that.
Most homes lost to wildland fire are lost to embers finding a way in. The four ways, in the order below.
Vents
Ember-resistant vents are among the least expensive items in the assembly, and among the most consequential. Unprotected attic and crawlspace vents are the classic way in.
Roof and its edges
Class A roofing is the baseline. The edge decides: where roofing meets sheathing, the open eave, the gutter holding a season of leaves.
Glazing
Radiant heat breaks windows before the structure ignites, and a broken window opens the house. Multi-pane and tempered glass materially raise that threshold.
The first five feet
The strip against the walls does more than anything further out. Non-combustible surfacing, no stored fuel, no combustible fence running into the house.
Access decides where the house sits
District rules on driveway width, turning radius, grade and water supply can decide where a building goes. On a tight or sloping parcel, that reshapes the scheme. Settle it at feasibility, not in plan check.
Insurance is now part of the brief
California’s wildfire insurance market has changed substantially; for many owners here, availability and premium now shape design. Document hardened assemblies and defensible space as they are built, and talk to your broker early: the answer can change what is worth specifying.
Rebuilding after a loss
A rebuild is not a renovation, procedurally or emotionally. Insurance scope and construction scope rarely match at first. Expedited pathways for rebuilding what stood often exist, and usually narrow if the scheme changes. The paperwork runs alongside the build.
We have done it: the Loureyro Property in Montecito, lost in the Thomas Fire, rebuilt from the ground up between 2019 and 2023. See the rebuild.
If that is where you are, start there. We will show you where the two scopes part, before either is committed.
Send us the address. We'll tell you the truth about it.
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