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Roofing Guide · San Rafael, CA

Class A Fire-Rated Roofs: What San Rafael’s Fire Map Asks of Your Roof

Roughly 1,800 San Rafael parcels are mapped High Fire Hazard Severity and about 4,100 more Moderate. In those zones, the roof is a regulated fire defense. Here is what that means in practice.

San Rafael’s hills are beautiful and, on the state’s fire maps, consequential: roughly 1,800 parcels fall in High Fire Hazard Severity Zones and about 4,100 in Moderate zones. California’s Wildland-Urban Interface code (Building Code Chapter 7A, and CRC Section R902 for residences) turns those map colors into roof requirements. If your home is in a mapped zone — and many owners have never checked — your next roof is not just a purchase. It is a compliance project with a fire rationale.

What does “Class A” actually mean?

Class A is the highest fire rating for a roof assembly — the whole system tested together: covering, underlayment, and deck. It is not a shingle label you can buy piecemeal. A Class A assembly resists severe fire exposure, including the ember showers that start most WUI home losses. Concrete and clay tile, metal, and Class A-rated architectural shingle systems are the common residential routes; some low-slope foam systems also carry Class A ratings as complete assemblies. The point to hold onto: the rating belongs to the stack, so substitutions mid-project can void it.

What else does Chapter 7A ask for?

  • Ember-resistant vents: attic and foundation vents are how embers enter houses; WUI rules require listed ember-resistant designs or fine corrosion-resistant mesh.
  • Covered valleys and edges: metal flashing and bird-stopping at tile edges close the gaps embers exploit.
  • Gutter and debris discipline: in fire country, a debris-filled valley is fuel stored on the roof — the storm-prep checklist doubles as fire prep.
  • Documentation: in mapped zones, keeping the assembly’s paperwork with the house file matters at resale (see our roof & resale guide).

How do you check whether your parcel is mapped?

The state’s Fire Hazard Severity Zone maps are public, and your roofer should check your parcel before materials are discussed — we do it as part of every free inspection in the hill neighborhoods. The map, not the vibe of the street, is the authority: two houses on the same road can sit on different sides of a zone line.

Not in a mapped zone? Class A is still the default we recommend anywhere a roof borders open space. The map is a legal minimum, not a physics boundary — embers do not check parcel lines.

If your mapped-zone roof is due, our replacement process specs the full compliant assembly — covering, underlayment, vents, and edge details — as one written line, because that is what the rating requires.

Fire-Roof FAQs

Class A Questions, Answered

Zones, assemblies, vents, and how to check your parcel.

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01 How many San Rafael homes are in fire hazard zones?

About 1,800 parcels are mapped High Fire Hazard Severity and roughly 4,100 more Moderate — a large share of the city’s hillside neighborhoods, including edges of Terra Linda, Peacock Gap, and the streets climbing from downtown and Dominican.

02 Does Class A mean a specific material?

No — it is a rating of the whole assembly: covering, underlayment, and deck tested together. Tile, metal, Class A shingle systems, and some foam systems can all achieve it. Swapping one component for a non-listed substitute can void the assembly’s rating, which is why we spec it as one written line.

03 Are ember-resistant vents really required?

In mapped zones under Chapter 7A, yes — vents must be listed ember-resistant designs or protected with fine corrosion-resistant mesh. Embers entering attic vents are a leading cause of WUI home loss, which is why the rule exists and why we treat vents as part of the roof project, not an accessory.

04 My roof is fine for years. Should I do anything now?

Two cheap things: verify your parcel’s zone (we will do it free), and keep valleys and gutters debris-free — in fire country, roof debris is stored fuel. The assembly upgrade itself happens at replacement time.

In a Mapped Zone?

We Verify Your Parcel as Part of the Free Inspection

Zone check, assembly spec, and ember-resistant venting in the written quote — no guessing about which rules apply to your street.

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Get In Touch

Book a Fire-Zone Roof Inspection

Tell us your neighborhood — Terra Linda’s edges, Peacock Gap, the hill streets — and we will check the map for your parcel.

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