---
title: "Replacing a Shingle Roof With Metal in California | NEMA Roofing"
description: "Replacing a shingle roof with metal: whether the shingles come off, which metal system to choose, and California permit, Class A fire and cool roof rules."
url: "https://nemaroofing.com/metal-roofing/upgrade-your-property-with-long-lasting-metal-roofing/"
updated: "2026-09-30"
---

**Replacing a shingle roof with metal comes down to five decisions: whether the shingles come off or stay under the metal, which metal system goes on, what the permit requires, whether the new roof must be Class A for fire, and whether its color must meet California’s cool roof values.** The rest of the job (flashing, vents, edges and gutters) follows from those choices. This guide walks through each one in the order a project runs. To have your roof assessed for the switch, call NEMA Roofing at [866-631-3366](tel:866-631-3366).

## What changes when a roof goes from shingles to metal?

Almost every part you can see. Shingles are small overlapping pieces nailed through the face; most metal roofs are long panels or large interlocking shingles fixed with clips or screws, so the details around them are different:

- **Flashing and trim.** Ridge, hip, valley, eave and rake pieces are made for the metal system, and the 2025 California Residential Code (section R908.5) requires rusted, damaged or deteriorated flashings, edgings, outlets and vents to be replaced rather than reused.
- **Pipe and vent openings.** Each roof penetration gets a boot or flashing made for metal panels.
- **Gutters and edges.** New eave trim is made for the metal system, and the gutter position under it is checked when that trim goes on.
- **Underlayment.** The metal maker’s instructions name the underlayment or separation layer; a shingle underlayment is not automatically right under metal.

## Should the shingles come off first?

California allows one sound layer of shingles to stay under a new roof when the metal system’s instructions permit it, and forbids it over two or more layers or over a wet or deteriorated roof (section R908.4). Our guide to [putting a metal roof over shingles](https://nemaroofing.com/metal-roofing/metal-roofing-the-durable-choice-for-your-home/) covers those conditions in detail. For a switch to metal, removal is usually the stronger choice when:

- the attic shows old leak stains or soft, sagging sheathing;
- the shingles are curled enough to make the surface uneven, which shows through flat panels;
- solar panels are planned for the new roof and you want the deck seen first;
- ventilation or insulation at the deck needs work, which is easier with the roof open.

## Which metal system replaces shingles best?

Homes coming off shingles usually choose between standing seam panels (concealed fasteners, long runs from ridge to eave), metal shingles or tiles stamped to look like other roofing, and exposed-fastener panels, often used on barns and outbuildings. The choice changes the look, the trim and how the roof is fastened, so settle it before the estimate. Our overview of [metal roof styles](https://nemaroofing.com/metal-roofing/metal-roofing-styles-mat-benef-ex/) compares the options, and [metal roofing vs traditional shingles](https://nemaroofing.com/metal-roofing/metal-roofing-vs-traditional-shingles-which-one-is-right-for-you/) helps if you are still deciding whether to switch at all.

## Fire rating and cool roof rules for the new metal roof

In areas under the 2025 California Wildland-Urban Interface Code, a roof covering put on in an alteration or repair must be at least Class A. Metal is treated as Class A without testing only when it sits on a noncombustible deck; on a wood deck, and on a wood deck with shingles left in place, the metal system needs its own Class A listing for that assembly. Ask for the listing before you sign.

California’s Energy Code counts a new metal surface as a roof replacement whether or not the shingles stay. On a steep-slope home in climate zones 4 and 8 through 15, which include the San Fernando Valley, the inland valleys and the Inland Empire, replacing more than half the roof calls for a color that meets the aged cool roof values unless an exception applies (such as R-38 ceiling insulation, or no ducts in the attic in zone 9). Coastal zone 6 towns like Oxnard and Santa Barbara carry no steep-slope cool roof requirement on a reroof.

## Permits for switching to metal

Changing the roof covering is a reroof, and a reroof normally needs a building permit. The rules come from the city or county where the house sits:

- **City of Los Angeles** (Woodland Hills, Tarzana, Encino and other Valley neighborhoods): LADBS handles reroofing as an Express Permit, without plan check, for a Class A or B covering under 6 pounds per square foot over solid sheathing; Very High Fire Hazard Severity Zones need Class A, and a home replacing more than half its roof needs a product certified by the Cool Roof Rating Council.
- **Unincorporated Riverside County**: a Re-Roof Permit covers installing, replacing or altering roof covering; when the roof is stripped to the sheathing, the deck is inspected before the new roof goes on, otherwise a final inspection closes the permit.
- **Carpinteria**: reroofing needs a city permit; only roof-coating repairs of 40 square feet or less are exempt.

## How a shingle-to-metal project runs

1. **Assessment.** Count the shingle layers, look at the deck from the attic, and measure the roof.
2. **System and color.** Pick the metal profile and a color, checking its Class A listing and cool roof rating where they apply.
3. **Permit.** File with the city or county, including those product documents.
4. **Removal or preparation.** Strip the shingles and replace damaged sheathing, or prepare the single sound layer as the metal maker’s instructions require.
5. **Underlayment and trim.** Install the specified underlayment, then eave and rake metal.
6. **Panels and flashing.** Set the panels, then the ridge, valleys, wall flashing and a new boot on every pipe.
7. **Inspection and records.** Pass the final inspection and keep the permit, product listings and warranty papers together. For what the crew does day by day, see [what to expect from a metal roofing installation](https://nemaroofing.com/metal-roofing/metal-roofing-installahat-xpect/).

## Switching to metal with NEMA Roofing

Across all five counties we serve (Los Angeles, Ventura, Santa Barbara, San Bernardino and Riverside), NEMA Roofing takes homes from shingles to metal, and our locations in Downey, Tarzana, Woodland Hills, Oxnard and Santa Barbara keep a crew near your town (see the [service areas page](https://nemaroofing.com/service-areas/)). We look at the shingle layers and the deck before recommending removal or not, and we price the metal system you choose line by line. Read more on our [metal roofing service page](https://nemaroofing.com/our-services/metal-roofing/), or call [866-631-3366](tel:866-631-3366).