Most asphalt shingle roofs last 20–30 years. But age alone doesn't tell the full story — the way a roof was installed, how well it was maintained, and what weather it has endured all play a role. Knowing when to replace rather than repair can save you thousands of dollars and prevent interior damage that's far more costly to fix.
Warning Signs Your Roof May Need Replacing
Shingles Are Curling or Buckling
Curling at the edges (called cupping) or buckling up the middle of a shingle are signs of moisture damage and age. A few problem shingles can be replaced, but widespread curling means the roof surface is failing.
Granule Loss in the Gutters
Asphalt shingles are coated in granules that protect the underlying mat from UV rays. As shingles age, those granules shed into your gutters. If you're cleaning out gutter grit that looks like coarse sand, your shingles are nearing the end of their life.
Daylight Through the Roof Boards
If you can see light through your attic ceiling, water can get in too. This level of deterioration — whether from rot, missing shingles, or failed flashing — typically requires full replacement.
Sagging Sections
A sagging roof deck is a structural issue, not just a cosmetic one. It often points to long-term moisture exposure that has rotted the decking and rafters beneath. Catch it early.
It's 20+ Years Old and Has Never Been Replaced
Even if your roof looks okay from the street, a 20-year-old asphalt shingle roof is living on borrowed time. Get a professional inspection before a storm makes the decision for you.
Repair vs. Replace: How to Decide
As a general rule: if the damage affects less than 30% of the roof and the deck beneath is sound, a repair is often the right call. If damage is widespread, the roof is near the end of its expected lifespan, or you're dealing with a second layer of shingles over an already-repaired roof, full replacement is usually more cost-effective.
A reputable contractor will walk you through both options and give you honest guidance — not just push for the bigger job.
What a Roof Replacement Involves
- Tear-off. The old shingles and underlayment are removed and the decking is inspected for rot or damage.
- Deck repair. Any damaged plywood or OSB is replaced before anything new goes on.
- Underlayment. A waterproof barrier is installed over the deck — this is your last line of defense if a shingle fails.
- Flashing. Metal flashing is installed or replaced around chimneys, skylights, and roof valleys.
- Shingles. New shingles are laid starting from the eaves up, overlapping to shed water.
- Cleanup and inspection. All debris is removed and the job is inspected for quality.
What Does a Roof Replacement Cost?
Replacement pricing depends on roof size, pitch, complexity, and material choice. Standard architectural asphalt shingles are the lowest-cost tier; metal, designer asphalt, and premium materials sit higher. Larger homes and steeper pitches always trend higher. Always get multiple written quotes that break out materials, labor, and disposal — and have any contractor inspect on-site before pricing.
Questions to Ask Your Contractor
- Are you licensed and insured in your state?
- What manufacturer warranty comes with these shingles?
- What workmanship warranty do you offer?
- Will you pull a permit if required by my municipality?
- How do you handle unexpected deck damage found during tear-off?