How long does each roofing material last?
| Roofing material | Estimated life (years) |
|---|---|
| Asphalt shingles (3-tab) | 20 |
| Asphalt shingles (architectural) | 30 |
| Wood shakes or shingles | 25 |
| Metal | 40 to 80 |
| Clay or concrete tile | 100+ |
| Slate | 60 to 150 |
| Built-up roofing (flat) | 30 |
| Modified bitumen (flat) | 20 |
| TPO (flat) | 7 to 20 |
| EPDM rubber (flat) | 15 to 25 |
Source: InterNACHI Standard Estimated Life Expectancy Chart. InterNACHI notes that these are guidelines for normal wear with recommended maintenance, not guarantees.
How does the weather in the Bay Area affect roof life?
Bay Area roofs live in several climates at once. Fog, shade and redwood litter keep West Marin, Mill Valley and parts of the Oakland and Berkeley hills damp, which lets moss lift shingles. Wind and salt air along San Francisco, Daly City and the coast corrode flashing and fasteners. Inland Contra Costa and the Santa Clara Valley bake through dry summers, and InterNACHI notes that hot climates drastically reduce asphalt shingle life.
How can I find out how old my roof is?
- Permit history. Most building departments can look up past permits for your address, including reroofs.
- Purchase paperwork. Your home inspection report and the seller's disclosures often note the roof's age or last replacement.
- Invoices and warranties. A roofing contract or manufacturer warranty registration shows the install date.
- A roofer's assessment. A licensed roofer can estimate remaining life from the materials and their condition, with photos.
How old are homes in the Bay Area?
Together these six counties have more than 1.3 million owner-occupied homes. Pre-war and post-war stock dominates San Francisco, Berkeley and Oakland, often with complex rooflines, chimneys or flat roofs. Marin and the Peninsula mixed 1950s–70s hillside and tract homes with older downtown neighborhoods, and Santa Clara County's large 1970s tracts — including many Eichlers with flat or low-slope roofs — tend to reach replacement age in waves.
What does roof age mean for my insurance?
Insurers use roof age in underwriting. Beginning January 1, 2028, SB 1301 bars an insurer from refusing or nonrenewing a policy solely because of roof age when the policyholder pays for an independent inspection showing at least five years of useful life left. See our insurance guide.
Frequently asked questions
How long does a shingle roof last?
InterNACHI estimates about 20 years for 3-tab asphalt shingles and about 30 years for architectural shingles under normal conditions with maintenance.
How long does a metal roof last?
InterNACHI's chart estimates 40 to 80 years for metal roofing.
How long does a flat roof last?
It depends on the system. InterNACHI estimates about 30 years for built-up roofing, 20 for modified bitumen, 7 to 20 for TPO and 15 to 25 for EPDM rubber.
How do I find my roof's age?
Check your city's permit history for your address, your purchase inspection report and disclosures, and any roofing invoices or warranty paperwork, or ask a licensed roofer to assess it.
Sources
Sources reviewed November 11, 2026. Figures are published estimates and official fees, not quotes. Confirm prices, permits and requirements with your contractor and building department. This page is general information, not legal or insurance advice.