Brentwood · Oakley · Antioch · Discovery Bay
Roof Replacement in Brentwood, CA
A reroof is the biggest roofing decision most homeowners make. This guide covers when replacement makes sense, the material choices for East County homes, permits and energy rules, solar panels, and how to compare bids.
Signs a roof needs replacing
- Leaks keep returning in different places.
- Asphalt shingles are curling, cracking or shedding granules across most of the roof.
- A tile roof's underlayment has failed broadly, not just in one area.
- The roof deck feels soft or sags in several spots.
- The roof is near the end of its expected life. InterNACHI's life-expectancy chart lists architectural asphalt shingles at about 30 years and notes that hot climates shorten asphalt life (InterNACHI).
Not sure? A roof inspection or our repair-or-replace guide can help before you commit.
Material choices for East County homes
| Material | Installed cost (national guides) | Notes |
|---|---|---|
| Architectural asphalt shingle | $4–$6 / sq ft | Most common reroof choice; check cool-roof rated colors (see below). |
| Concrete tile | $7–$19 / sq ft | Heavy and long-lived; the roof structure must support the weight. |
| Tile lift-and-relay (reuse tiles, new underlayment) | $2.75–$3.50 / sq ft labor | Often an alternative to full replacement on tile roofs. |
| Standing-seam metal | $9–$16 / sq ft | Long life; higher upfront cost. |
Sources: HomeGuide (shingle, metal), This Old House (concrete tile), Fixr (lift and relay). Checked October 2026. Full cost guide.
What a reroof involves
- Inspection and written estimate, including how many layers come off and an allowance for deck repair.
- Permit pulled by the contractor.
- Solar panels removed by a solar company, if you have them.
- Tear-off to the deck, deck repairs, new underlayment, flashing and vents.
- New roofing installed; in-progress and final inspections by the building department.
- Solar reinstalled, site cleanup and magnet sweep for nails.
Permits and California rules that apply
Permits. Antioch says a re-roof permit is required (City of Antioch). Oakley issues re-roof permits over the counter, usually the same day (City of Oakley). Contra Costa County, which covers Discovery Bay, requires a permit for all re-roof installations and repairs, with in-progress and final inspections (Contra Costa County). Brentwood lists re-roofs as a building permit type (City of Brentwood).
Cool roofs (Title 24). East Contra Costa is in California climate zone 12. For steep-slope reroofs there, the energy code generally requires a cool-roof-rated product when more than 50% of the roof or more than 2,000 sq ft is replaced, whichever is less, with several exceptions, including heavy roofs such as most concrete tile, adequate attic insulation, or a radiant barrier (Energy Code Ace, BayREN). Your contractor and the building department confirm what applies to your house.
Fire rating. When more than 50% of a roof is replaced within a year, California requires the whole roof covering to meet the fire-rating class for its area (Health & Safety Code §13132.7).
Solar panels and reroofing
If you have solar, the panels must be removed and reinstalled (often called detach-and-reset). Fixr estimates $200–$300 per panel, or about $2,800–$4,800 for a 14–16 panel system (Fixr). Antioch notes that solar removal and reinstallation needs its own permit (City of Antioch). If you're adding solar soon and your roof is older, replacing the roof first avoids paying for detach-and-reset later.
Comparing reroof bids
Ask every roofer to price the same scope: tear-off layers, underlayment type, flashing, vents, deck-repair allowance per sheet, permit, cleanup and warranty terms. California limits the down payment on home-improvement contracts to 10% of the price or $1,000, whichever is less (CSLB).
Roof replacement questions
What is the average cost of replacing a roof in California?
There's no official statewide figure. Angi lists California's average for a shingle roof replacement at about $15,200, the highest of the states it shows. National guides put architectural shingles at $4–$6 per square foot installed and concrete tile at $7–$19 per square foot.
Is $30,000 too much for a roof?
Not necessarily. A large or steep roof, a tile roof, deck repairs, or solar panels that must be removed and reinstalled can push a reroof well past $20,000. Compare itemized bids for the same scope rather than judging the total alone.
How long does a roof replacement take?
Many single-family reroofs take a few days once work starts, but permits, material delivery, weather and solar detach-and-reset can add time. Ask for the schedule in writing.
Do I need a permit to replace my roof in Brentwood?
Plan on it. Brentwood lists re-roofs among its building permit types, Antioch says a re-roof permit is required, Oakley issues re-roof permits over the counter, and Contra Costa County (Discovery Bay) requires a permit for all re-roof installations. Your contractor normally pulls it.
East Contra Costa communities we cover
Requests come from homeowners across the eastern end of Contra Costa County, along Highway 4 and the Delta.
Request a roof replacement estimate
Tell us what's going on with your roof. We pass your request to an independent local roofing contractor serving East Contra Costa, who contacts you to inspect and quote. There's no cost to send a request.
- Takes about a minute
- No obligation to hire
- Ask for a written, itemized estimate