Quick answer
Repair your roof when it’s under about 15 years old and the damage is limited to one area, like a few shingles, a pipe boot, or a flashing leak. Replace it when the roof is 20+ years old, the wear is spread across several slopes, the decking is soft, or you’ve repaired the same problems more than once. A roofer’s inspection will tell you which applies.
Key takeaways
- Localized damage on a younger roof means repair. Widespread wear on an older roof means replacement.
- A common rule: if repairs would cost more than about a third of a new roof, replacement is usually the better value.
- Repeated leaks in different spots mean the roof as a whole is failing.
- Storm damage may change the math if insurance covers a replacement.
When your roof leaks or a storm rips off some shingles, the big question is whether you can fix it or need a whole new roof. Here’s how roofers make that call, so you can tell whether the advice you’re getting makes sense.
When is a roof repair enough?
A repair is usually the right choice when:
- The roof is relatively young, generally under about 15 years for asphalt shingles.
- The damage is in one area: a few blown-off shingles, a cracked pipe boot, a leak at the chimney flashing, or a small spot of storm damage.
- The surrounding shingles are healthy. They’re flexible, have their granules, and lie flat.
- The decking underneath is solid.
Common repairs include replacing damaged shingles, resealing or replacing flashing, swapping out pipe boots, and fixing vents. These are usually affordable and, on a sound roof, they last. See our roof repair service for the kinds of fixes we handle.
When is it time to replace the roof?
Replacement usually makes more sense when:
- The roof is 20 years old or more, or close to the end of its rated life.
- Wear is spread out. Curling, cracking, or bald shingles show up on several slopes, not just one.
- You keep having leaks, especially in different places.
- The decking is soft or sagging.
- Granules are piling up in your gutters.
- Storm damage covers a large part of the roof.
For a fuller checklist, see signs your roof needs replacement.
How do you compare the cost?
Look past the price of today’s fix and think about the next several years.
A common rule of thumb: if repairs would cost more than roughly a third of a new roof, or you expect to keep paying for repairs, replacement is usually the better value. Repeated repairs on an old roof add up, and each leak risks damage to decking, insulation, drywall, and belongings that costs far more than the roof work.
On the other hand, replacing a 10-year-old roof because of one leak around a pipe boot is a waste of money. A good roofer should tell you that.
What about partial replacement?
Sometimes one slope is badly damaged and the rest of the roof is fine, so replacing just that section is an option. It has trade-offs:
- New shingles rarely match weathered ones exactly.
- The joint between new and old sections needs careful work.
- Manufacturer warranties typically cover only the new section.
It can make sense for a younger roof with damage on one side. For an older roof, the remaining sections will need replacement soon anyway.
Does storm damage change the decision?
It can. If hail or wind damaged your roof and your homeowners insurance covers it, the insurer may pay for a full replacement minus your deductible, even if the roof wasn’t otherwise ready. Have it inspected and documented before deciding. Learn more in does insurance cover roof damage?
How do you get an honest answer?
The best way to decide is a hands-on inspection by a roofer who will show you photos and explain the reasoning. Be wary of a contractor who recommends replacement without showing you why, or one who keeps patching a roof that has clearly worn out.
Boxwood offers free roof inspections in Hartselle, Decatur, and across Morgan County. If a repair will do the job, we’ll tell you. If it’s time to replace, we’ll show you why and give you a detailed written estimate.
Frequently asked questions
How much life does a roof repair add?
A good repair on a healthy roof can last as long as the rest of the roof. A repair on a worn-out roof only fixes that one spot. The shingles around it keep aging, and new leaks often show up nearby within a year or two.
Can a roofer just replace the shingles and not the decking?
On a full replacement, the old shingles come off and the decking is inspected. Only sheets that are rotted or damaged are replaced. Solid decking stays. That’s why estimates usually include a per-sheet price for any decking that needs replacing.
Is it bad to put new shingles over old ones?
A second layer is allowed by many building codes, but it adds weight, traps heat, hides rotted decking, and can affect warranties. A full tear-off is almost always the better long-term choice.
About the author
Jon Berry owns Boxwood Roofing & Restoration, a licensed, family-owned roofing contractor in Hartselle, AL, serving Morgan County homeowners since 2017.
