A listing that says "newer roof" is telling you what the seller believes, not what anyone has checked. You can narrow it down yourself in about ten minutes on a showing, and you can pin it down with paperwork before your inspection period ends. Do both. A roof that turns out to be near the end of its life changes what the house is worth to you, and it can change what it costs to insure.
The report engine behind this site puts asphalt and similar roofing at roughly 15 to 25 years of service life depending on material, and a full replacement at $8,000 – $25,000+. That range is why the question deserves a real answer rather than a guess.
Start with what the roof is made of
Age only means something against the material. A 15-year-old asphalt shingle roof and a 15-year-old slate roof are at very different points in their lives, so the first thing to note is the covering itself: asphalt shingles, metal, tile, slate, wood shakes, or a low-slope membrane on a flat section. Your inspector will write this down. Under the American Society of Home Inspectors Standard of Practice, which many inspectors work to (ASHI SoP, section 6.1), the inspector must describe in writing the type and material of the roofing and its condition.
If the house has a flat or low-slope section, that part is usually a different material from the rest and may have been replaced on a different date. Treat it as its own roof. The flat roof insurance guide covers why underwriters look at those sections separately.
What you can see from the ground and the gutters
None of these give you a date. Together they tell you whether "about ten years old" is plausible or wishful.
- Granules in the gutters or at the bottom of the downspouts. Asphalt shingles shed their mineral coating as they wear. A little is normal on any roof; drifts of it are not.
- Shingle edges that curl up or cup down, tabs that are cracked or missing, and lines of exposed nail heads.
- Patches that do not match. A section in a different color usually means a repair. A repair is not a replacement, and it does not reset the age of the rest of the roof.
- Dark streaks. Often algae, which is mostly cosmetic. It is also the thing most often misread from aerial photos, as the guide to insurers' aerial roof photos explains.
Count the layers at the edge
Look at the roof edge where it meets the gutter, or at the gable ends. A single layer of shingles sits flat and thin. A second layer laid over the first, called a roof recover, shows a thicker, slightly lumpy edge.
This matters more than it looks, because of a building code rule. Under the International Residential Code, section R908.3.1.1, a roof recover is not permitted where the existing roof already has two or more applications of any type of roof covering. So if the house already has two layers, the next roof must be a full tear-off down to the deck, which adds the cost of tearing off the old layers. Some places are stricter than the model code: the City of Norman, Oklahoma, for example, publishes a state amendment that allows no second layer of asphalt shingles at all.
A second layer can also hide the age of the first. If the seller says the roof is eight years old and you can see two layers, ask which one is eight years old.
Go into the attic
If the attic is accessible, it is the most honest view of the roof you will get on a showing. Look at the underside of the roof deck with a flashlight for water stains, dark or damp patches around chimneys and vents, and daylight coming through where it should not. Stains do not tell you the age of the covering above them, but they tell you whether it has been doing its job.
Pin it down with records
The physical clues give you a range. Paper gives you a date. In rough order of strength:
- A re-roofing permit, if one was pulled. Many jurisdictions require a permit to re-roof, and the closed permit carries a date. Not all do: the City of Norman, Oklahoma, states that it does not require a permit for roofing work, though the work must still meet the adopted codes. So no permit on file is not proof that nothing was done. The method for finding a property's permit history in any county is in the permit lookup guide.
- The contractor's invoice and any manufacturer warranty registration. Ask the seller for them in writing.
- The seller's disclosure. Where your state requires a disclosure form, read what it says about the roof. The questions vary from state to state, and an answer on the form is the seller's knowledge, not a measurement.
- Old listing photos. If the house sold before, the photos from that sale often show the roof. A different color or style then is a strong clue it has been replaced since.
The full order of evidence, and what to do when the county has no record, is in how to prove a roof's age for insurance. That guide is written for proving the age to a carrier; the same paperwork answers a buyer's question.
What your inspector will and will not tell you
A general home inspection is a look at condition, not a dating service. The ASHI Standard of Practice says the inspector is not required to determine "the age, life expectancy or remaining useful life of systems and components" (section 15.2), and is not required to walk on roofs (section 6.3). Many inspectors will still give an opinion if you ask, but you have to ask, and it is an opinion.
If the answer matters to your offer, and on an older roof it usually does, ask the inspector directly for an estimate of remaining life, or have a licensed roofer look at it during your inspection period and put the estimate in writing.
Why the number matters for insurance
Homeowners insurance quotes commonly ask for the roof's age, and an older roof can make a policy harder or more expensive to get. Ask for a quote on the specific address while you are still under contract, not after closing.
Florida has written part of this into law. Under Florida Statutes section 627.7011(5), an insurer may not refuse to issue or renew a homeowner's policy solely because of the age of a roof that is less than 15 years old. For a roof at least 15 years old, the insurer must let the homeowner have it inspected first, and may not refuse solely because of roof age if the inspection shows 5 years or more of useful life remaining. The statute also defines roof age as the last date on which 100 percent of the roof's surface was built or replaced, which is the legal version of the point above: patching part of a roof does not make it a newer roof. Outside Florida, ask your own carrier how it treats roof age, and get the answer in writing.
A short list for the showing
- What is it made of, and is there a flat section with its own age?
- One layer or two at the edge?
- Granules, curling, missing tabs, mismatched patches?
- Stains or daylight in the attic?
- Ask the seller for the permit, the invoice and the warranty.
- Ask your inspector, out loud, for a remaining-life estimate.