Win a Free Noncombustible Pedestrian Gate
Enter now

Zone Zero Decks & Patios Requirements

California's Zone Zero draft does not require replacing deck or patio surfaces. What it does require is that the ground underneath decks, balconies and stairs stays free of vegetation and combustible items — and it measures Zone 0 outward from the edge of an attached deck, not from your wall. Decks and patios remain significant ember accumulation and ignition points during wildfires.

Check your address

Decking replacement is not required

The draft sets material requirements for combustible fences, gates and outbuildings. Decks are not on that list — an attached deck is treated as part of the structure, so it is the boundary Zone 0 is measured from rather than an object inside it. Noncombustible decking in concrete, pavers, stone, porcelain tile or metal is a real fire-hardening upgrade; it is not something this draft obliges you to do.

Under-deck space must be kept clear

Open space beneath elevated decks is a prime ember accumulation zone. The draft requires that the areas underneath decks, balconies, pergolas and stairs be kept free of vegetation and combustible items. Enclosure is not required — the rule package itself calls screening the deck base best practice rather than an obligation.

Timing: 3 years, and 3–5 years

Two different clocks, and neither is running yet. Keeping the area under a deck free of vegetation and combustible items falls in the three-year group. The five feet of vegetation-free ground spanning out from the deck edge falls in the three-to-five-year group, on a timeline your local fire agency sets. Both start from an effective date that does not exist yet.

[background image] image of suburban neighborhood

What Zone Zero requires for decks and patios

Wood decks and patios within Zone Zero present two distinct fire risks: the decking surface itself can ignite from embers, and the enclosed space beneath elevated decks accumulates debris that can burn for extended periods and ignite the structure from below.

The August 19, 2026 Board of Forestry final draft (approved 8–0; not yet law) does not require replacing the decking surface itself. The draft names combustible fences, gates and outbuildings and sets material requirements for those — decks are not on that list. What it does change is where Zone 0 begins: an attached deck is treated as part of the structure, so the five feet is measured outward from the edge of the deck, not from the wall.

For elevated decks, the space beneath the deck is equally important. Embers can travel under a deck and ignite accumulated debris, dry leaves, or stored items. What the draft requires is that this area be kept free of vegetation and combustible items at all times. Fully enclosing it with fiber cement, metal or concrete goes further than the rule asks — a reasonable choice, but not a requirement.

Attached stairs are part of the structure for Zone 0 purposes, which means Zone 0 is measured outward from their edge. The draft does not require replacing wood or composite railings or stair stringers. Aluminum, steel or cable railings and metal or concrete stringers resist ember ignition better, but under this rule they are upgrades rather than obligations.

Decks and Patios: Frequently Asked Questions

Common questions about Zone Zero deck and patio compliance, answered clearly.

Does my whole deck need to be replaced or just the part within 5 feet?

The draft does not set a material requirement for the decking surface at all, so no part of it has to be non-combustible under this rule. The measurement point is the part people get wrong: an attached deck counts as part of the structure, so Zone 0 runs five feet outward from the edge of the deck, not from the wall. A large deck therefore pushes the regulated ground further into the yard — which affects planting and storage around it, not the deck itself.

If I am rebuilding anyway, is composite decking like Trex a good choice?

The draft does not require you to rebuild, so treat this as an upgrade question rather than a compliance one. Most standard composite decking, including Trex, is combustible and will ignite from embers. Some composite products carry Class A fire ratings — check the OSFM Building Materials Listing for California-approved products, and look for WUI-rated composite if you want a wood-look alternative to concrete or pavers.

Can I keep my wood deck if I store nothing underneath?

No. Read against the operative text, the draft does not require replacing the decking surface. It sets material requirements for combustible fences, gates and outbuildings, and an attached deck is not among them — it is defined as part of the structure, which is the boundary Zone 0 is measured from. What the draft does require is that the area underneath stays free of vegetation and combustible items, and that the five feet spanning out from the deck edge stays vegetation-free. Your local jurisdiction may impose more than the state draft does, so check your local rule.

If I choose to upgrade, what are the most cost-effective materials?

Concrete pavers are typically the most cost-effective option for ground-level patios. For elevated decks, aluminum decking and porcelain tile over concrete board offer good value. KAYU Batu hardwood is a premium option with a Class A OSFM rating that keeps a natural wood appearance. None of these are required by the state draft — verify what your local AHJ actually asks for before specifying anything.

What about outdoor furniture and items stored on the deck?

Combustible patio furniture, cushions, rugs, and stored items within Zone Zero should be moved inside or to a non-combustible storage area during Red Flag Warning conditions. The August 19, 2026 final draft specifically mentions petroleum-based trash containers and patio cushions as items that should be moved indoors during Red Flag days.

Do I have to replace my wood deck?

There is no statewide effective date. The Board of Forestry approved the final draft on August 19, 2026, and the filing with the Office of Administrative Law was later withdrawn, so no state Zone 0 deadline is currently running. Some jurisdictions have their own ordinances with real dates — San Diego binds existing structures in the Very High Fire Hazard Severity Zone by February 28, 2027. Check your local rule rather than the state draft.

Start here

Do not leave this page without a next step.

The Board approved the final draft August 19, 2026. It is not yet law. Check your parcel, grab the checklist, or ask us what applies to your property.

Check your addressGet the PDF checklistContact Us

Ask about your deck or patio

Contact Us
Decks and Patios

Find out what your deck actually requires

Most of what the draft asks for around a deck is clearing, not construction. Before you budget for a rebuild, it is worth knowing whether your address is even in a fire hazard zone, and what your local jurisdiction requires on top of the state draft.

Check your address