A metal roof usually lasts 40 to 70 years (opens in a new tab), and sometimes longer. That is far past asphalt shingles, which we plan at 18 to 25 years in Maryland. How long yours lasts depends on the metal, the finish, the screws and flashing, and who put it on.
The short version
- A good metal roof runs 40 to 70 years. Steel and aluminum are usually 30 to 50 years or more, and copper is in a class of its own.
- The panels rarely wear out first. The screws, the sealant and the flashing do.
- Scratches in the paint, debris sitting on the roof and screws driven too hard or too loose all shorten the life.
- A warranty tells you what the maker will cover, not how long the roof will last.
- One quick look every year is the cheapest way to get the full number of years.
How long does a metal roof last compared with shingles?
A metal roof lasts about twice as long as asphalt shingles, and often more. This Old House puts metal at 40 to 70 years (opens in a new tab) and says it can outlast its own warranty. Asphalt shingles come with a 15 to 30 year warranty, and in Maryland we plan on 18 to 25 years before a replacement.
That gap is the whole reason people look at metal. Buy one roof instead of two and the higher price starts to make sense. It also means a metal roof can outlive your time in the house, so the question is less “will it last” and more “will it last the way it was built to.”
How long does each kind of metal last?
Steel and aluminum usually last 30 to 50 years or more, and copper can last 100 years or longer. The numbers below come from This Old House’s guide to metal roofs, and they assume the roof was put on properly and looked after.
| Metal | How long it can last | Worth knowing |
|---|---|---|
| Steel | 30 to 50 years or more (opens in a new tab) | Has a coating over the metal to fight rust, so the finish matters |
| Aluminum | 30 to 50 years or more (opens in a new tab) | Softer than steel, so it dents more easily |
| Copper | 100 to 200 years (opens in a new tab) if well kept | Costs the most by a wide margin |
If a roofer quotes you a lifespan, ask which metal it is for. “Metal” covers a lot of ground.
Does the warranty tell you how long it will last?
No. A warranty is a promise about defects in the product, not a forecast of how many years you will get. This Old House notes metal roofs often come with 30 to 50 year warranties (opens in a new tab) and can outlast them, which tells you the number on the paper is not the number on the roof.
We see the same thing with shingles. A “50-year” label is a manufacturing warranty, not a field life. The workmanship warranty from whoever installs your roof matters more than the one from the factory, so ask to read both before you sign.
What makes a metal roof wear out early?
Poor installation is the biggest reason a metal roof dies young. This Old House says improper installation can lead to leaks and a shorter life (opens in a new tab), and that matches what we say about every roof: the crew decides the lifespan more than the brand does.
A few specific things to watch:
- Screws driven wrong. The Department of Energy’s Building America guide says to not underdrive or overdrive the fasteners (opens in a new tab). Too tight crushes the washer, too loose leaves a gap.
- Scratches in the paint. Bare metal rusts. This Old House suggests touching up scratches in the finish (opens in a new tab) before rust gets going.
- Leaves and standing water. Corrosion can come from ponding water and debris (opens in a new tab), so a roof under a heavy tree needs a brush-off now and then.
- The wrong screws. The same guide says to pick screws and accessories that are chemically compatible (opens in a new tab) with the panel, so two metals do not eat at each other.
Exposed screw panels, the kind with visible screw heads, have one extra weak spot: the rubber washer under every head. It is the part that wears out first, and we cover it in why metal roof screws leak.
Which part of a metal roof fails first?
Usually not the metal. The flashing details and the sealant around them tend to give up decades before the panels do. Caulk is a consumable with a 5 to 10 year life, so any detail that depends on it to keep water out is a leak that is already scheduled.
That is why we push for real mechanical flashing, where the metal itself sheds the water, over a bead of sealant that someone has to redo. On a roof that should run 40 years or more, the caulk will be replaced several times. A roof with caulked chimney and pipe details will need repairs while the panels still look new.
Is a metal roof worth it if you may move?
It depends on how long you plan to stay. Standing seam metal typically costs two to two and a half times what asphalt shingles do, and our metal roof cost article walks through where that money goes.
If this is your long-term home, the extra years are the payoff. If you might sell in ten years, you will not use most of that life. Either way, the number that matters is how many years your roof has left, not how many it started with.
How do you get the full life out of a metal roof?
Look at it once a year and fix small things early. This Old House recommends a yearly roof inspection (opens in a new tab) whatever the material, to catch debris or damage before it causes a leak.
Here is what that check should cover:
- Scratches or bare spots in the paint
- Leaves or branches sitting on the panels or in the valleys
- Screws that have backed out or washers that look dry and cracked
- Sealant around vents, pipes and the chimney that has split or pulled away
Our free roof inspection includes a walk on the roof and a written report with photos. It is a visit from a company that also installs roofs, so treat it as a second opinion, not a verdict.
Common questions
Can a metal roof last 100 years?
Copper can, and This Old House says it can last 100 to 200 years if it is well kept. Steel and aluminum are usually put at 30 to 50 years or more, with 40 to 70 years for metal roofs overall. Anything beyond that is the exception.
Does a metal roof last longer than a shingle roof?
Yes, by a wide margin. A metal roof is usually 40 to 70 years, and we plan asphalt shingles at 18 to 25 years in Maryland. The metal roof only gets there if the screws, finish and flashing are done well.
Does a metal roof need to be replaced or just repaired?
Often it needs repairs, not replacement. Screws, washers and sealant are the parts that wear, and they can be fixed without touching the panels. A full replacement is for a roof with widespread rust or panels that are past saving.
Do metal roofs rust?
They can, where the paint is scratched or where water and leaves sit. Steel has a protective coating over the metal, so a scratch through it is where rust starts. Touching it up early keeps it from spreading.
What to do next
If you are weighing metal for a new roof, our metal roofing installation page explains what we do and where a metal roof makes sense. If you already have one and want to know how much life is left, ask for the free inspection and we will look at the screws, the flashing and the finish.
