Building decks in Altadena after the Eaton Fire

Altadena lost more than most in January 2025, and the rebuild here runs on a different clock from the Westside. Almost every deck we get asked about in Altadena now is part of putting a house back together.

Altadena is unincorporated Los Angeles County, so permits go through LA County rather than a city building department. That matters for your timeline and for who you end up talking to. It sits in a Very High Fire Hazard Severity Zone, in the foothills directly below the San Gabriels, which is the terrain that produces the wind-driven ember runs that took the neighborhood.

In January 2026 California consolidated its wildfire-zone construction rules into the California Wildland-Urban Interface Code, replacing Chapter 7A of the building code and Section R337 of the residential code. What it regulates is the walking surface, meaning deck boards and stair treads, not the framing underneath. And the requirement isn't a flame-spread number off a spec sheet. The deck surface has to come from a product carrying a California State Fire Marshal listing, tested under SFM Standard 12-7A-4, which puts burning embers on the deck instead of only measuring how fast flame travels across it.

That distinction matters more here than almost anywhere, because embers are what happened in Altadena.

Decking we build with that carries a listing: TimberTech AZEK Vintage and Landmark, both Class A with no conditions. Kayu Batu, also called Red Balau, Class A with no conditions. Ipe, but only through specific listed suppliers, because the ratings vary between them and the species alone tells you nothing. Trex Transcend, Select, Transcend Lineage and Refuge are all listed, but each one needs the exterior wall covering next to the deck to be noncombustible or ignition-resistant. Trex Enhance isn't listed at all.

We check the product against the State Fire Marshal's building materials listing before it goes on a material schedule, not after plan check flags it.

What the terrain asks for

Altadena runs uphill. Lots along the foothills, Chaney Trail, the canyons, the streets above Altadena Drive, usually need elevated decks with real footings and engineered framing rather than a slab-level build. Where a deck is elevated, the code requires the underside enclosed to grade in compliant material. That's the detail that gets missed until inspection day.

If you're rebuilding and want a straight answer about what will and won't pass, call (818) 345-2866.