How do I know my roof needs replacing?
Eleven warning signs that signal an Eugene roof is at or past end of life, plus the ones that look bad but are usually repair situations.
Start with the age
The single most reliable indicator is your roof's age relative to the material lifespan. Standard 3-tab asphalt: 14-18 years in Eugene's canopied neighborhoods, 16-20 in sunnier locations. Architectural asphalt: 20-26 years with maintenance, 18-22 without. Standing seam metal: 40-70 years and you almost certainly aren't reading this article if you have one. Cedar shake: 25-35 with consistent maintenance, 15-20 without. If you don't know your roof's age, pull the permit record at Eugene B&PS or Lane County, residential roofing permits are public record and date-stamped.
Granule loss in the gutters
Asphalt shingles are coated with ceramic granules that protect the underlying asphalt and provide fire resistance. As shingles age, granules loosen and wash off. Check your gutters and the area under downspouts for accumulations of coarse sand-like material. Some granule loss is normal on a new roof (excess manufacturing granules); significant granule loss on a 10-plus-year-old roof says the shingles are nearing end of life. Bare patches where the black asphalt substrate shows through indicate urgent replacement. South-facing and west-facing Eugene slopes that get the most direct sun are typically the first to show this.
Curling, cupping, and lifted tabs
Shingles distort two ways. Cupping is when the edges turn upward (looks like a saucer). Clawing is when the center buckles while the edges stay flat. Both indicate moisture damage, inadequate ventilation, or material failure. Lifted tabs along the eaves usually mean wind damage; lifted tabs across the field of the roof usually mean adhesive failure from age. If you can see curled or cupped shingles from the ground across multiple slopes, the roof is past systemic repair.
Visible moss mats (or worse, dead moss)
Surface moss is treatable. Heavy established moss with thick mats has likely damaged the shingles underneath: roots lift edges, water gets under, the shingle delaminates. Dead gray moss that's been sitting on the roof for a couple of years is often a sign the underlying material is past treatment. A contractor who removes a test patch can tell you whether the shingles beneath are sound or crumbling.
Sagging ridge line
Stand back from the house and look at the ridge from a distance. A perfectly straight ridge is what new construction looks like; a slight dip in the middle of a long span is normal on older homes; a noticeable wave or pronounced sag is a structural concern that warrants immediate professional evaluation. In Eugene, ridge sag most commonly comes from prolonged moisture exposure rotting the deck or undersized rafters. From the attic, look for dark stains, soft spots, or visible rot on the underside of the decking, those confirm what the ridge line is telling you.
Water stains on interior ceilings or walls
Active leaks show as ceiling stains, peeling paint near rooflines, or musty odours in the attic. A single leak in one spot can be a flashing repair. Multiple leaks in different locations, or recurring leaks despite previous repairs, point to systemic failure. Inspect the attic during daylight, pinpoints of light penetrating the deck mean holes or gaps above. In Eugene the most common interior symptoms come from chimney flashing failure or valley flashing deterioration, both of which can be repair situations on a younger roof and replacement triggers on an older one.
Rising heating bills (and the roof is the suspect)
A failing roof often compromises the home's thermal envelope before visible leaks appear. If your heating costs have crept up over several years without changes to your heating system or insulation, the roof may be losing its insulating function. Deteriorated shingles, water-damaged attic insulation that's lost loft, or inadequate ventilation all contribute. An energy audit can confirm whether the roof is the weak point.
Eleventh sign: your neighbors are reroofing
Eugene homes built in the same tract development typically reach end of roof life within 2-3 years of each other. If five houses on your block have been reroofed in the last two years, yours is statistically next. Not a definitive sign by itself, but worth a professional inspection if you're at year 18-plus in a Eugene neighborhood where the dominant housing stock is 1960s-1980s ranches.