Key Takeaways
A roof leak is the last-stage warning sign, not the first. Here are 10 earlier signs your roof needs attention — granule loss, curling shingles, and more.
By the time a roof actively leaks, it's usually been failing for a while. These are the earlier warning signs — visible from the ground, the attic, or your utility bill — that tell you it's time for a closer look before a leak forces the issue.
Signs You Can Spot From the Ground or Gutters
- Granule loss collecting in gutters and downspouts. Asphalt shingles shed some granules as they age, but heavy accumulation means the shingle's protective surface is wearing thin.
- Curling or cupping shingle edges. Edges that lift or cup upward signal the shingle is drying out and losing its seal against wind-driven rain.
- Algae or moss streaking on north-facing slopes. Dark streaking is usually gloeocapsa magma, an algae that thrives in shaded, moisture-prone areas — cosmetic at first, but a sign of persistent moisture.
- A sagging roofline. Any visible dip or sag in the roof deck, rather than a straight line, points to a structural or decking issue that needs prompt attention.
- Cracked, split, or brittle shingle tabs. Especially common on older 3-tab roofs, cracked tabs are a direct entry point for water.
- Rust or corrosion at chimney and vent flashing. Discolored, flaking metal flashing has lost its ability to shed water cleanly.
Signs You Can Spot From the Attic or Your Energy Bill
- Daylight visible through the attic decking. If you can see light through the roof from inside the attic, water can get through the same gaps.
- Missing or damaged step and valley flashing. A flashlight check of valleys and chimney intersections from the attic can reveal gaps a ground-level look would miss.
- Nail pops creating raised bumps under shingles. As decking shifts seasonally, fasteners can back out, creating small bumps that eventually crack the shingle above them.
- Rising energy bills tied to poor ventilation. Unbalanced soffit intake and ridge exhaust ventilation traps heat and moisture in the attic, driving up cooling costs in summer and contributing to ice dams in winter.
Any one of these on its own may not mean immediate replacement — but multiple signs together, or a roof already near or past its expected lifespan, are reasons to get a professional opinion. Our guide to how long a roof actually lasts and our breakdown of repair vs. replace can help you figure out which side of that line your roof is on. For the earlier-stage version of this same walk-through, see our spring roof inspection checklist, and browse more posts in Roof Maintenance & Inspection.