Repair or replace? Signs your roof is wearing out

What wears a roof out in Oregon

It isn't one big storm. It's years of rain followed by summer sun. The oils in asphalt shingles dry out, the shingles get brittle, and the protective grit on top washes into the gutters. Shade and moss speed it up: moss grows under shingle edges, lifts them, and holds water against the roof long after the rain stops.

That's why roofs here often age faster than the number on the package, and why two houses on the same street, built the same year, can have roofs in very different shape. The one under the fir trees is usually the one in trouble.

The signs you can see from the ground

• Curling or lifted corners. Shingles that no longer lie flat have lost their flexibility, and wind gets under them.
• Bald patches. Dark, smooth spots where the grit is gone. The grit is what protects the asphalt from the sun.
• Grit in the gutters. A little at the downspout is normal on a new roof. A steady supply on an old one means the shingles are shedding.
• Moss that keeps coming back. Especially when the shingles stay lifted after it's cleaned off.
• Cracked or missing shingles. A few after a storm is a repair. New ones every winter is a pattern.
• A wavy or sagging roofline. This one matters most. It can mean the wood underneath has been wet for a long time.

The signs you can see from the attic

If you can get into the attic safely, take a flashlight up on a dry day and again after a hard rain. Look for:

• Dark stains or trails on the underside of the roof boards
• Damp or matted insulation
• Daylight showing where it shouldn't
• A musty smell that wasn't there before

Leaks in more than one place are the clearest sign of all. One leak is a repair. Leaks in three rooms are a roof telling you it's done.

When a repair makes sense

If the problem is in one place, like failed flashing, a split vent boot or a few shingles taken by wind, and the rest of the roof still lies flat and holds its grit, fix the problem. There's no reason to replace a sound roof because of one bad detail. A good roofer will tell you that, even though the repair is the smaller job.

When it stops making sense

When the shingles are worn out everywhere, a patch just moves the leak. You pay for a repair this winter and another next winter, and you still own an old roof. At that point the money is better spent once.

Age matters here for a second reason. Some insurance companies look harder at roofs once they reach about twenty years. If your insurer has asked about the age or condition of your roof, that's worth bringing up when someone comes out to look at it.

You can't settle it from the driveway

Some of this shows from the ground, but the deciding details don't: how brittle the shingles are, the state of the flashing, whether the wood underneath is soft. That takes someone on the roof. Ask whoever looks at it to show you photos of what they found.

Questions worth asking any roofer

• What's your CCB number? (In Oregon you can look it up on the state's license search in a minute.)
• Will I get the scope in writing, with what's included and what isn't?
• What happens if you find soft decking once the old roof is off, and how is that priced?
• What's covered by the shingle manufacturer's warranty, and what's covered by your own workmanship warranty? They aren't the same thing.
• Who will be doing the work?

For what a full replacement involves, see our roof replacement page.