How do you know a roof needs to be replaced?
Short answer. The clearest signs are bare patches where shingles have lost their granules, curling or cracking across whole slopes, a sagging roofline, daylight or water stains in the attic, and leaks that keep returning in new places. When those show up on a roof that is 15 to 25 years old, replacement is usually more economical than repeated repairs.
Signs ranked by urgency
- Sagging or soft spots. A dip in the roofline or a deck that flexes underfoot means the wood beneath has been wet for a long time. This one should not wait.
- Active leaks in more than one spot. A single leak often traces to one pipe boot or flashing. Several leaks usually mean the whole system is failing.
- Missing or cracked shingles across several slopes. Shingles that snap instead of bending have dried out and will keep breaking in every windstorm.
- Curling and cupping. Edges turning up or middles lifting let wind-driven rain get underneath.
- Granule loss. Heavy granules in the gutters and dark bare spots on the shingles mean the asphalt is now exposed to the sun.
- Attic clues. Damp insulation, mildew smell, stained rafters or pinpoints of daylight.
What changes before and after
Before photos of a worn roof usually show uneven, patchy color, lifted tabs and wavy shingle lines. After a full replacement you should see straight courses, uniform color, new ridge caps, new metal at the edges, and fresh pipe boots and flashing, while inside the attic the stains stop growing. Take your own before photos of every slope and the attic; they help with insurance questions, a future sale and any warranty issue.
Georgia heat speeds all of this up, especially on south and west slopes and over poorly vented attics, as explained in heat and humidity and roof life. Compare what you see with signs you need a new roof.