Roofing in California

Repair when damage is localised — a few slipped tiles, one flashing leak — and the roof is under about two-thirds of its expected life. Replace when leaks recur in different places, more than roughly 30% of the covering is failing, or repair quotes start approaching a third of replacement cost. A good roofer will show you photos from the roof to justify either answer.

Dry, settled weather — and before your region's storm or rainy season, not after it starts. Roofers book out weeks or months ahead of peak season, so schedule inspections early; shoulder-season slots are often cheaper and easier to get.

Yes, over time — moss holds moisture against the surface, lifts tile and shingle edges, and accelerates frost damage. Have it removed by soft washing or manual scraping, never high-pressure washing, which strips granules and forces water under the covering. Zinc or copper strips slow regrowth.

Typical service lives: asphalt shingles 15-30 years, concrete tile 40-60, clay tile and slate 60-100+, metal 40-70, flat membranes (felt, EPDM, TPO) 15-30. Underlayment and flashings usually fail before the covering itself, which is why old roofs leak even with intact tiles.

Tear-off and disposal, underlayment spec, flashing replacement (not reuse), ridge and valley details, a unit price for replacing rotten decking discovered mid-job, scaffolding or edge protection, and cleanup with a magnetic nail sweep. A quote missing the deck-repair unit price is the classic setup for large mid-job extras.

Flashing is the metal detailing that seals joints — around chimneys, valleys, vents, skylights and wall junctions. These joints move and collect water flow, so flashing fails long before the main covering. If a roofer proposes reusing old flashing on a full replacement, push back.

Most homeowners pay $9,000-$18,000 for a standard asphalt shingle replacement, with the full range running roughly $6,000 to $30,000+ depending on size, pitch and region. Metal roofs typically run $15,000-$45,000. Per-square (100 sq ft) pricing of $450-$1,100 installed is the common quoting unit.

For sudden storm damage, usually yes — but many insurers now pay only depreciated actual-cash-value on roofs past 10-15 years old, not full replacement cost. Check your policy's roof schedule, document damage immediately, and be cautious with contractors who want to 'handle the claim for you.'